Did you know…?

Orcas (formerly known as killer whales), Orcinus orca, are actually dolphins. They are the largest of the dolphin family (Family Delphinidae with about 32 species, including the dolphins, pygmy killer whales, Feresa attenuata, and false killer whales, Pseudorca crassiddens). Next to humans, orca are the most widely distributed mammal. Orca inhabit all oceans of the world but are most numerous in the Arctic, the Antarctic and areas in nutrient-rich cold water upwellings. They have been sighted along the shores of Washington, Oregon, California, Baja California, and along the eastern coast of the United States. More...

Sharks attack some 50-75 people each year worldwide, with perhaps 8-12 fatalities, according to data compiled in the International Shark Attack File (ISAF). external Although shark attacks get a lot of attention, this is far less than the number of people killed each year by elephants, bees, crocodiles, lightning or many other natural dangers. On the other side of the ledger, we kill somewhere between 20-100 million sharks every year through fishing activities.

Of the 350 or so shark species, about 80% grow to less than 1.6 external m and are unable to hurt people or rarely encounter people. Only 32 species have been documented in attacks on humans, and an additional 36 species are considered potentially dangerous.

Almost any shark 1.8 external m or longer is a potential danger, but three species have been identified repeatedly in attacks: the great white, tiger, and bull sharks. All three are found worldwide, reach large sizes and eat large prey such as marine mammals or sea turtles. More attacks on swimmers, free divers, scuba divers, surfers and boats have been reported for the great white shark than for any other species. However, some 80% of all shark attacks probably occur in the tropics and subtropics, where other shark species dominate and Great white sharks are relatively rare.

An estimated 50-80% of all life on earth is found under the ocean surface and the oceans contain 99% of the living space on the planet. Less than 10% of that space has been explored by humans. 85% of the area and 90% of the volume constitute the dark, cold environment we call the deep sea. The average depth of the ocean is 3,795 external m. The average height of the land is 840 external m.

“Currently, scientists have named and successfully classified around 1.5 million species. It is estimated that there are as little as 2 million to as many as 50 million more species that have not yet been found and/or have been incorrectly classified.” – SOURCE external

According to World Register of Marine Species (WoRMS) external there are currently 199,146 named marine species.

So, there are at least 199,146 marine species but there are most likely at least 750,000 marine species (50% of 1.5 million species) and possibly as many as 25 million marine species (50% of 50 million species).

The oceans cover 71% (and rising) of the Earth’s surface and contain 97% of the Earth’s water. Less than 1% is fresh water, and 2-3% is contained in glaciers and ice caps (and decreasing).

90% of all volcanic activity occurs in the oceans.

The speed of sound in water is 1,435 external m/sec – nearly five times faster than the speed of sound in air.

The highest tides in the world are at the Bay of Fundy, which separates New Brunswick from Nova Scotia. At some times of the year the difference between high and low tide is 16.3 external m, taller than a three-story building.

Earth’s longest mountain range is the Mid-Ocean Ridge more than 50,000 external km in length, which winds around the globe from the Arctic Ocean to the Atlantic, skirting Africa, Asia and Australia, and crossing the Pacific to the west coast of North America. It is four times longer than the Andes, Rockies, and Himalayas combined.

The pressure at the deepest point in the ocean is more than 11,318 external tons/sq m, or the equivalent of one person trying to support 50 jumbo jets.

The top ten feet of the ocean hold as much heat as the entire atmosphere.

The lowest known point on Earth, called the Challenger Deep, is 11,034 external m deep, in the Marianas Trench in the western Pacific. To get an idea of how deep that is, if you could take Mt. Everest and place it at the bottom of the trench there would still be over a mile of ocean above it. The Dead Sea is the Earth’s lowest land point with an elevation of 396 external m below sea level.

Undersea earthquakes, volcanoes and landslides can cause tsunamis (Japanese word meaning “harbor wave”), or seismic sea waves. The largest recorded tsunami measured 60 external m above sea level caused by an 8.9 magnitude earthquake in the gulf of Alaska in 1899 traveling at hundreds of km/hr.

The average depth of the Atlantic Ocean, with its adjacent seas, is 3,332 m; without them it is 3,926 m. The greatest depth, 8,381 external m, is in the Puerto Rico Trench.

The Pacific Ocean, the world’s largest water body, occupies a third of the Earth’s surface. The Pacific contains about 25,000 islands (more than the total number in the rest of the world’s oceans combined), almost all of which are found south of the equator. The Pacific covers an area of 179.7 million sq km external.

The Kuroshio Current, off the shores of Japan, is the largest current. It can travel between 40-121 external km/day at 1.6-4.8 external kph, and extends some 1,006 external m deep. The Gulf Stream is close to this current’s speed. The Gulf Stream is a well known current of warm water in the Atlantic Ocean. At a speed of 97 external km/day, the Gulf Stream moves a 100 times as much water as all the rivers on earth and flows at a rate 300 times faster than the Amazon, which is the world’s largest river.

A given area in an ocean upwelling zone or deep estuary is as productive as the same area in rain forests, most crops and intensive agriculture. They all produce between 150-500 grams external of Carbon per square meter per year.

The sea level has risen with an average of 10-25 external cm over the past 100 years and scientists expect this rate to increase. Sea levels will continue rising even if the climate has stabilized, because the ocean reacts slowly to changes. 10,000 years ago the ocean level was about 110 external m lower than it is now. If all the world’s ice melted, the oceans would rise 66 external m.

The density of sea water becomes more dense as it becomes colder, right down to its freezing point of -1.9°C external unlike fresh water which is most dense at 4°C external, well above its freezing point of 0°C external. The average temperature of all ocean water is about 3.5°C external.

Antarctica has as much ice as the Atlantic Ocean has water.

The Arctic produces 10,000-50,000 icebergs annually. The amount produced in the Antarctic regions is inestimable. Icebergs normally have a four-year life-span; they begin entering shipping lanes after about three years.

sea gull

Air pollution is responsible for 33% of the toxic contaminants that end up in oceans and coastal waters. About 44% of the toxic contaminants come from runoff via rivers and streams.

Each year, three times as much rubbish is dumped into the world’s oceans as the weight of fish caught.

Oil is one of the ocean’s greatest resources. Nearly one-third of the world’s oil comes from offshore fields in our oceans. Areas most popular for oil drilling are the Arabian Gulf, the North Sea and the Gulf of Mexico.

Refined oil is also responsible for polluting the ocean. More oil reaches the oceans each year as a result of leaking automobiles and other non-point sources than the oil spilled in Prince William Sound by the Exxon Valdez or even in the Gulf of Mexico during the Deepwater Horizon/BP oil spill external.

The record for the deepest free dive is held by Jacques Mayol external. He dove to an astounding depth of 86 external m without any breathing equipment.

A mouthful of seawater may contain millions of bacterial cells, hundreds of thousands of phytoplankton and tens of thousands of zooplankton.

The Great Barrier Reef, measuring 2,300 external km in length covering an area more extensive than Britain, is the largest living structure on Earth and can be seen from space. Its reefs are made up of 400 species of coral, supporting well over 2,000 different fish, 4,000 species of mollusc and countless other invertebrates. It should really be named ‘Great Barrier of Reefs’, as it is not one long solid structure but made up of nearly 3,000 individual reefs and 1,000 islands. Other huge barrier reefs include the barrier reefs of New Caledonia, the Mesoamerican (Belize) barrier reef, and the large barrier reefs of Fiji. The largest coral atoll complexes occur in the Maldive-Lakshadweep ecoregion of the central Indian Ocean and in Micronesia.

Fish supply the greatest percentage of the world’s protein consumed by humans and most of the world’s major fisheries are being fished at levels above their maximum sustainable yield; some regions are severely overfished.

More than 90% of the trade between countries is carried by ships and about half the communications between nations use underwater cables.

The swordfish and marlin are the fastest fish in the ocean reaching speeds up to 121 external kph in quick bursts; the bluefin tuna (Thunnus thynnus) may reach sustained speeds up to 90 external kph.

Blue whales are the largest animals on our planet ever (exceeding the size of the greatest known dinosaurs) and have hearts the size of small cars.

The oarfish (Regalecus glesne external), is the longest bony fish in the world. It has a snakelike body sporting a magnificent red fin and can grow up to 17 external m in length, it has a distinctive horselike face and blue gills, and is thought to account for many sea-serpent sightings.

Many fish can change sex during the course of their lives. Others, especially rare deep-sea fish, have both male and female sex organs.

One study of a deep-sea community revealed 898 species from more than 100 families and a dozen phyla in an area about half the size of a tennis court. More than half of these were new to science.

Life began in the seas 3.1 billion to 3.4 billion years ago. Land dwellers appeared approximately 400 million years ago, relatively recently in geologic time.

Because the architecture and chemistry of coral is so similar to human bone, coral has been used to replace bone grafts in helping human bone to heal quickly and cleanly.

The Ocean

Our ocean covers 72% (and rising) of this small planet and is home to most of the globe’s biomass, or living matter, and biodiversity. We know that from bacteria to plankton to the blue whale, life in the ocean greatly affects life on land, yet we know very little about the ocean. At least 80% is yet to be explored.

Global water and air volume
Conceptual computer artwork of the total volume of water on Earth (left) and of air in the Earth’s atmosphere (right) shown as spheres (blue and pink). The spheres show how finite water and air supplies are. The water sphere measures 1,390 kilometres across and has a volume of 1.4 billion cubic kilometres. This includes all the water in the oceans, seas, ice caps, lakes and rivers as well as ground water, and that in the atmosphere. The air sphere measures 1,999 kilometres across and weighs 5,140 trillion tonnes. As the atmosphere extends from Earth it becomes less dense. Half of the air lies within the first 5 kilometres of the atmosphere.

 

Dolphins (toothed whales)

Marine Life / Marine Vertebrates / Structures & Adaptations to Marine Living »
By Kerry G. Beck, May 2010

Description & BehaviorAtlantic white-sided dolphins, Lagenorhynchus acutus

They’re the acrobats and court jesters of the sea, troops of aerial spinners and wave dancers. Their long shining sleek bodies jet high into the air as they perform a grand ballet with tails propelling them as they skim each wave against the continuous horizon. Mesmerizing to watch, dolphins have been gliding, flipping and dancing into our hearts for centuries.

While no one is exactly sure why these marine mammals perform their fascinating aerial feats, it’s well documented that the playful stunts are an integral part of their behavior. They are well credited throughout history for their playful and social nature as well as superior smarts. Closely related to whales and porpoises, there are over 50 species of dolphin found worldwide.

During the early morning hours, spinner dolphins off Kauai’s Na Pali Coast can be seen leaping from the water at great speeds. The louder the tourists in passing catamarans cheer and clap the more elaborate and lasting the performance, some twirling many times in the air before ever splashing back down. In Florida’s Key West, the more common bottlenose varieties might be seen playing catch with a clump of seaweed or working collaboratively in groups to circle in on and whip fish up into the air to feed on. They spend a great deal of time “fishing,” as an adult male may consume up to 30 pounds or more of fish in a single day. Though we often picture them propelling up to the clouds, they have been known to dive as deep as at least 300 external meters into their world below the sea surface.

The pantropical spotted dolphin, Stenella attenuata

Having their bellies as built-in surfboards, they will readily catch a ride on a bow wave and have been doing so for many years. Ancient Greek sailors believed a dolphin riding in their wake was a good omen for a smooth voyage. This was not the case for thepink dolphin of the Amazon River where the indigenous people held if a dolphin was encountered it may tempt unknowing humans into the water and carry them to an underwater world of no return. Sadly and ironically, it’s the pink dolphin facing a fate of no return. That dolphin species, which is in fact pink and has a hump rather than a more common dorsal fin, has landed on theInternational Union for Conservation of Nature Endangered Species List external. Excessive boat traffic, pollution and habitat loss have brought more than a bad omen to this amazing creature. Unfortunately, similar factors pose a threat to all Clymene dolphins, Stenella clymenedolphin species in the oceans of the world. Able to travel at top speeds, swimming over 40 externalkilometers per hour, dolphins can’t always out swim the threats they face.

While dolphins seem to be quite the chatterboxes, with their wide range of clicks and whistles, hearing may be their most important asset with a technique called echolocation. They have no sense of smell, so eyesight and hearing are essential for hunt and survival. In addition to excellent eyesight, they can hear frequencies many times more than a human. Like bats, dolphins are able to bounce high-pitched sounds toward an object and listen for the echo back, allowing them to get a map of their environment, find food and navigate. But increasing interfering factors like noise pollution, underwater testing conducted in the search for oil and gas sources, naval sonar and live firing exercises are problematic. All these factors can damage a dolphin’s hearing and put great stress on them as they try to escape an unsafe environment. Some even suffer decompression sickness as they try to surface too quickly to escape the noise. Recently researchers at the Bottlenose Dolphin Research Institute external conducted a study confirming a link between dolphin vocal emissions, social activities and social signals. And what they can’t hear they can certainly feel.

Irrawaddy dolphins, Orcaella brevirostrisThe dolphin’s skin is very smooth and jam-packed with nerve endings making it many times more sensitive to touch than a human’s. Shedding a layer of skin every two hours, they are very delicate and easily hurt by rough surfaces or garbage and other objects that simply shouldn’t be in their environment. You’ll never find a barnacle hitching a ride on a dolphin. But just imagine how painful it might be to try to wrestle free from a fishing drift or gill net, flee irritating and potentially poisonous contaminants in the water or heal after a run-in with a motor boat blade or jet ski.

Only a small portion of the population may be purposely hunting dolphin but anyone can take action to protect them from harm. Preserving the dolphin isn’t only beneficial to their overall survival but could also directly benefit modern medicine. Recently at a meeting of the American Association for the Advancement of Science external the National Marine Mammal Foundation external reported on a study external concluding that blood chemistry of a fasting dolphin resembled that of humans with diabetes. The researchers concluded that dolphins could be the most realistic model for studying diabetes in humans.

Common bottlenose dolphins, Tursiops truncatusIn addition to all of their captivating characteristics, dolphins are really smart. Anyone who has ever worked with dolphins has noted their natural ability to learn, problem solving ability and sometime mischievous streak. They’ll also stick together in times of trouble. In the wake of Hurricane Katrina, eight bottlenose dolphins were forced out to sea when their marine facility was destroyed by the storm. Before being rescued two weeks later, all eight dolphins survived injuries and stuck together becoming a symbol of hope and strength for the Gulf Coast, a region with an ecosystem that is now under brutal attack again, this time from the devastating oil spill.

What They Look Like
Although their color varies among species, the basic coloring of dolphins is a shade of gray with a white underbelly. Their large mouth, curved into a wide smile, houses up to 250 small teeth. They can vary in size from 1.2 external m and 40 external kg to 9.5 external m and more than9,000 external kgs. Dolphins breath through a blowhole on the top of their head. They only have a few hairs at the tip of their snout, or rostrum, at birth. However, the boto or Amazon river dolphin, which has poor eyesight, does have some small hairs on the rostrum believed to aide as an additional tactile sense. Looking at a dolphin up close there are many unique features beyond the curved mouth that appears set in a constant and mischievous smile. They have a streamlinedfusiform external body built for speed and equipped with the tail fin, or fluke, for propulsion. Using their entire tail section they control direction with the dorsal fin, found on some species, providing extra stability. No dorsal fin is the same on any dolphin, it’s a key distinguishing feature like a unique face or fingerprint.

How They Swim
Fast! The speedy marine mammals, can swim up to 40 external kilometers per hour or faster for an hour or longer. They use their tail fin, or fluke, for propulsion and pectoral fins and tail for direction. Those who have a dorsal fin use that for added stability.

How They Communicate
Capable of producing a wide repertoire of sounds, the dolphin uses nasal air sacs located just below the blowhole. Three distinct categories of sound include frequency modulated whistles, burst-pulsed sounds and clicks. Dolphins communicate with their whistles and burst-pulsed sounds and some can identify themselves using a signature whistle. Clicks are mostly directional when they use echolation. For example, a click rate increases when a dolphin approaches an object of interest. These are some of the loudest sounds made by marine mammals.

Do They Sleep?
Dolphins sleep with only one brain hemisphere in slow-wave sleep at a time, which allows them to stay conscious enough to breathe and keep a watch out for any predators or other threats. In captivity dolphins have been found to enter a full sleep state where both eyes are closed and there is no response. This may be because they are not preyed upon in captivity.

World Range & Habitats

Where They Live
There are about forty-eight species of ocean dolphins and five species of river dolphins. They are found in all oceans of the world where they can be found predominantly in the shallower seas of the continental shelves. Very social animals, they tend to live in pods of up to a dozen members. However, in some areas where there is an abundance of foods, superpods can form with more than 1,000 dolphins. Dolphins also will stay and try to take care of any injured or ill members of their group. They also have been found assisting other species and protecting swimmers from sharks by swimming protective circles around the swimmers or charging the sharks to stave them off.

Feeding Behavior (Ecology)

What They Eat
Fish, fish and more fish. An adult male orca can eat up to 290 external kgs of fish or more in one day. Squid and an occasional crustacean are added delicacies on a dolphin’s menu. They are all carnivores. To feed many times members of a pod will surround and circle a school of fish. Dolphins have also been observed corralling fish into shallow water where they can be more easily captured. They can also cooperatively herd fish into a “bait ball” where the hungry dolphins take turns plowing into the ball to feed on the stunned fish.

While there are few threats to dolphins from other marine life who want to eat them, they occasionally will fall prey to some larger shark species including bullsgreat whites and tiger sharks. The largest dolphin is the orca, commonly known as the killer whaledue to its huge size, is the ocean’s very top predator.

Orcas (formerly known as the killer whale), Orcinus orca

Some infrequent incidents of orca’s attacking smaller dolphins or calves have been documented. Perhaps one of the most inexplicable threats comes from Japan where thousands of bottlenose dolphins are slaughtered each year for their meat.

Rough-toothed dolphins, Steno bredanensisLife Histories

How They Reproduce
Dolphins are viviparous, meaning that their eggs develop inside the female and the embryo derives nutrition from the mother. Dolphins mate belly to belly. Because this is also a social behavior, some species engage in lengthy activity, however, copulation is brief, about 10 seconds, and may be repeated several times over a short period. In some cases males will fight viciously over females during the breeding season and a hierarchy based on size is generally established among males. Females become sexually mature at five to 12 years of age, while males are mature at nine to 13 years. Their reproductive organs are located on the underside of the body. Males have two slits, one concealing the penis and one further behind for the anus. The female has one genital slit, housing the vagina and the anus. A mammary slit is positioned on either side of the female’s genital slit. Dolphins usually produce offspring once every two to three years. For most dolphin species, gestation lasts for 12 months and lactation lasts from 12 to 18 months. Despite the long nursing period, young dolphins begin eating solid food when they are less than six months old. Mother and calf often remain closely associated until the young dolphin is four or five years old.

Conservation Status/Additional Comments

Yangtze river dolphins, Lipotes vexilliferHow You Can Help
Other than some humans, dolphins have few natural enemies. Yet their future is uncertain. Many dolphins are killed each year when they get entangled in fishing nets. Others are suffering due to contamination of their environment and death and injury after run-ins with boats and jet skis. In Japan dolphins are herded toward shore and killed with harpoons in bloody hunts, a practice that conservation organizations have condemned. Pesticides, heavy metals, plastics and other agricultural pollutants also harm their environment. There are a number of organizations engaged in ways to protect the future for the dolphin. Visit the sites listed below under Further Research and read more on how you can help ensure their future.

Taxonomy

There are an estimated 53 species of dolphin in 24 genera. Dolphins are related and classified in the following way:

Kingdom Animalia   Phylum Chordata   Subphylum Vertebrata   Class Mammalia   Subclass Theria   Infraclass Eutheria  Order Cetacea   Suborder Odontoceti (toothed whales) 

Hybrid dolphins

Three dolphins were found beached on the coast of Ireland in 1933 and were reportedly hybrids between Risso’s and bottlenose dolphins. This mating was apparently later repeated in captivity producing a hybrid calf. A bottlenose dolphin and a rough-toothed dolphin in captivity were also reported to have produced hybrid offspring. A common dolphin-bottlenose dolphin hybrid is kept at SeaWorld in California. Other dolphin hybrids are also kept in captivity around the world or have been reported in the wild, such as a bottlenose-Atlantic spotted dolphin hybrid. The best known dolphin hybrid is the wolphin external, a false killer whale-bottlenose dolphin hybrid which is fertile. Two wolphins are currently captive at the Sea Life Park in Hawaii; the first was born in 1985 from a male false killer whale and a female bottlenose dolphin. Wolphins have also apparently been observed in the wild.

The vaquita, Phocoena sinus

Evolution

Dolphinswhales and porpoises have all evolved from land dwelling ancestors, like all marine mammals, most likely of theArtiodactyl order external. The ancestors of dolphins are thought to have entered the water about fifty million years ago, in the Eocene external epoch.

Long-beaked common dolphins, Delphinus capensisInterestingly, the bones in dolphin pectoral fins external closely resemble those of the human hand and their skeletons also have two small pelvic bones which appear to be vestigial external hind legs. In 2006 an unusual bottlenose dolphin was captured in Japan external with small pelvic fins on each side of its genital slit, which scientists believe to be a more pronounced development of these vestigial hind limbs.

Evolving in water over time, dolphins became more streamlined and lost their hind limbs in favor of tails that enable them to swim faster and dive deeper after prey. For example, the common dolphin can swim at speeds up to 64 kph external.

Further Research

Conservation, research and news:

Photos:

The plant kingdom external is made up of multicellular, photosynthetic external eukaryotes external.These multicellular organisms contain specialized cells that perform different tasks. Algae are some of the simplest aquatic plants, often referred to as seaweed in the marine environment. Marine algae are abundant throughout the ocean and can either float freely or cling to substrate such as rocks and reefs. The majority of seaweeds are classified as red algae (~6,000 species). There are also brown algae (~1,750 species) and green algae (~1,200 species). None of the algae species are known to be poisonous external, and many species are harvested for human consumption. Find out more at The Seaweed Site. external

Phytoplankton

Phytoplankton external are microalgae that form an essential component of the marine food chain. These single-celled plants provide nourishment to many marine species and they also play an important role in regulating the amount of carbon in the atmosphere. There are two main types of the larger phytoplankton species: Diatoms and Dinoflagellates. Smaller phytoplankton categorized as nanoplankton and picoplankton external.

diatom - Coscinodiscus graniiDiatoms

The cell walls of diatoms are made of silica formed into their characteristic “pillbox” shape. Diatoms are composed of two valves or frustules, one on top of the other, within which the living matter of the diatom is found. Diatoms are either found singly where each individual lives in a single box, or found in chains. Diatoms reproduce by dividing in half. One half is attached to the top valve, the other is attached to the bottom valve. Once the division takes place, each half creates a new valve to form another whole. The new valve is secreted in the old valve, therefore the average size of each diatom is reduced with every new generation. It is thought that as many as 50,000 species of diatoms have inhabited the earth. They occur in both fresh and salt water. See also “What are diatoms?” external

Dinoflagellates

Dinoflagellates are the other primary form of large phytoplankton with about 2,000 species. Unlike diatoms, dinoflagellates are mobile through the use of a flagella. Also unlike diatoms, they do not have an external skeleton made of silica, however they are protected by cellulose. dinoflagellate - Ceratocorys sp.Dinoflagellates are typically solitary and do not form chains like diatoms. Like the diatom they reproduce through fission. Once divided, each half retains half of the original cellulose armor and replaces the missing half to form a new whole. Some dinoflagellates can produce toxins that are released into seawater. When there are large blooms, a phenomenon known as red tide occurs. In some cases increased levels of dinoflagellate toxin may cause other marine life to die. The symbiotic algae found in many corals, or zooxanthellae, are actually a non-mobile species of dinoflagellate. Dinoflagellates have strong bioluminescence and have been a source of fascination for sailors and other mariners as their ships pass through waves which become lit up by these organisms at night. See also “What are dinoflagellates?” external

Algae - Visit AlgaeBase (123,313 species and infraspecific names):http://www.algaebase.org external

As mentioned earlier, algae are photosynthetic eukarotes that are either unicellular, colonial, or multicellular. Algae with at least some multicellular members are grouped into three Divisions external of the plant kingdom: Division Rhodophyta (red algae), Division Phaeophyta (brown algae) and Division Chlorophyta (green algae). These three groups are thought to have evolved from different groups of unicellular ancestors. Red and brown algae species are most commonly marine; green algae are found in abundance in both marine and freshwater.

Division Rhodophyta (Red Algae) external

Red algae grow as single-celled plants or plants that grow as filaments, branched plants, broad flat plates, and ruffled plants. They come in a variety of sizes, but most red algae are small. All species attach to substrate such as rock or coral and sometimes to an animal shell or even another algae species.

Giant Kelp, Macrocystis pyrifera - Channel IslandsDivision Phaeophyta (Brown Algae) external

Brown algae contain the largest and most complex algae plants. Pacific kelp are a brown algae species. There are no unicellular or colonial forms of brown algae. Brown algae stores food reserves as a substance called laminarin, similar to a lesser known species of gold algae in the division Chrysotphyta. Brown and gold algae also have in common the presence of flagellated cells of both sperm and motile spores. Brown algae are commonly found attached to substrate in cool, shallow waters near the shore in temperate and subpolar regions. Some forms of brown algae have developed adaptations to survive life on the coast where they may be pounded by surf or submerged then exposed with the tide. Large brown algae are used as shelter for some bottom-dwelling animals. They also provide serve as substrate for other algae that grow as epiphytes, or plants that grow on other plants.

Division Chlorophyta (Green Algae) external

Chlorophyta (green algae) is the most biodiverse of the algaes with species that grow in a variety of forms and in a variety of habitats. They are typically small and simple, with many single-celled species, some that form branched filaments, hollow balls of cells, or broad, flat sheets. Some species attach to sandy shores by secreting a calcareous cement rather than holdfasts that might shift with the sand and become unstable.

Ulva compressa
Ulva rigida (Sea Lettuce) external

Seagrasses external, unlike seaweed, are flowering plants that live submerged in the marine environment. There are an estimated 50 species of seagrasses worldwide, most of which are found in the tropics. Seagrass beds grow in shallow waters forming thick beds that provide an important habitat for marine life in temperate and tropical seas. These habitats vary in size and abundance from isolated patches to a continuous area that grows for miles. In waters with a lot of wave activity, beds tend to be patchy. In calmer waters, seagrass beds tend to carpet the seafloor.

Seagrasses typically grow as long, thin leaves with air channels that grow up from a creeping rhizome. Seagrasses are found from the mid-intertidal region to depths of 50 external m. Most species grow in soft substrates, such as sand, and form a dense mat of entwined rhizomes and roots that not only secure the plant, but also stabilize sediment. They also absorb wave motion and slow currents.

Kelp Beds: Forests of the Sea

As mentioned previously, Pacific kelp is a large species of brown algae. Kelps grow throughout the cold temperate regions of the world. They are known as kelp beds where there is no surface canopy and kelp forests where they form a canopy.

Like other algae species, kelps attach to the substrate using a holdfast. The holdfast extends into a stem or trunk ending in broad, flat blades. A gas-filled pneumatocyst is found beneath the blade, which floats the kelp at the surface. They take up nutritents generated by the constantly moving seawater.

Macrocystis and Nereocystis are the two genera that make up most kelp forests on the Pacific coast of North America. These enormous kelps grow upward through the water column to 20-30 external m in length. These plants grow toward the surface where they can spread their blades to obtain sunlight, which often blocks sunlight from other organisms. Beneath the canopy, an “understory” of algae is found, which forms another layer.

Kelps grow extremely quickly under the right conditions. Growth rates of external cm/day have been recorded in Nereocystis luetkanan (Scagel 1947) and Macrocystis pyrifera has been recorded at 50 external cm/day (North 1971) on the California coast. Surprisingly, despite this rapid growth rate and high rate of productivity, relatively few marine species graze directly on the kelp.



Orcas (Killer Whales), Orcinus orca

Description & Behavior

Orcas (formerly known as killer whales), Orcinus orca (Linnaeus, 1758), are actually dolphins. And they are the largest of the dolphin family (Family Delphinidae ~ 32 species, including what we normally consider dolphins, pygmy killer whales, Feresa attenuata, and false killer whales, Pseudorca crassiddens). Orcas reach a maximum length of over external m and can weigh up to7,257 external kg. Because of their fierce reputation, orca are sometimes called the Ballena asesina (“assassin whale”) by the Spanish. They were referred to as “whale killers” by sailors who witnessed their attacks on larger cetaceans, and over time this name was changed to “killer whales.” They are called this not because they harm humans but because they do sometimes kill other whales, hunting them in packs thereby earning the title “Wolves of the Sea.”

Killer whales, Orcinus orca, Rolf Hicker Nature Photography

Orcinus is probably derived from Orcus external, an ancient mythological Roman god of the netherworld—a reference to the ferocious reputation of this animal. Orca literally means “the shape of a barrel or cask” in Latin, likely due to the orca’s body shape.

Orca are seen usually traveling in pods of between 3-25 individuals, usually including at least one large male (a male is shown in the foreground of the photo above, notice the difference in the shapes of the dorsal fins).

World Range & Habitat

Next to humans, orcas are the most widely distributed mammal. Orcas inhabit all oceans of the world but are most numerous in the Arctic, the Antarctic and areas in nutrient-rich cold water upwellings. They have been sighted along the shores of Washington, Oregon, California, Baja California, and along the eastern coast of the United States.

In addition to cold water areas, orcas have also been seen in warm water areas such as Hawaii, Australia, the Galápagos Islands, the Bahamas, and the Gulf of Mexico. Such sightings are infrequent, but they do demonstrate the orca’s ability to venture into tropical waters. Even more surprising, orcas have been seen in fresh water rivers around the world such as the Rhine, the Thames, and the Elbe. One orca was even reported to have even traveled some 177 external km up the Columbia River in search of fish.

Although orca can be found in both the open ocean and coastal waters, they primarily inhabit the continental shelf in waters less than 200 external m deep. In cold water areas, their distribution is limited by seasonal pack ice.

Feeding Behavior (Ecology)

Active and opportunistic, orca are THE apex predators external in the ocean.

Orcas, killer whales, Rolf Hicker Nature Photography

Fishessquidssealssea lionswalrusesbirdssea turtlesotterspenguins, cetaceans (both mysticete and odontocete), polar bearsreptiles, and even a moose have all been found in the stomach contents of orcas.

And, as their common name implies, the remains of other orcas have also been found in the stomachs of these “killer whales.” It is uncertain why these animals are cannibalistic.

The diets of orcas vary from one region to another. In the Antarctic, orcas eat about 67% fishes, 27% marine mammals and 6% squid. In the Bering Sea near Alaska, they eat about 65% fishes, 20% squids and 15% marine mammals.

The diets of resident and transient orcas differ as well. Resident pods eat a wide variety of fishes and rarely seek out marine mammals. Transient groups primarily eat marine mammals and occasionally eat fishes. Adult orcas eat approximately 3% to 4% of their body weight in food per day; fully weaned calves can eat up to approximately 10% of their body weight during growth periods.

Much like packs of wolves or prides of lions, orcas often hunt cooperatively in pods for food. They work together to herd prey into a small area before attacking. When hunting a large whale, a pod of orcas may attack from several angles.

Life History

Orca (Killer Whale) NursingStudies of orcas in marine zoological facilities suggest that females become sexually mature when they reach 4.6-4.9 external m, at about 6-10 years. Males usually become sexually mature when they reach about 5.5-external m, at about 10-13 years. Breeding may occur in any season, but it is most common in the summer. In the North Atlantic, mating seems to peak in October and November; in the western North Pacific, mating seems to be at its highest between May and June. The gestation period of an orca is about 17 months—the longest known of all cetaceans. Based on limited data collected from populations at sea and in zoological facilities, a female may bear a calf every 3-5 years, although a decade may pass before some have another successful birth. Calves are born in the water. The majority of deliveries seen by humans have been tail-first births, although a head-first birth has been observed. Size estimates of captive-born orcas suggest that calves average 2.6 external m in length and weigh between 136-181 external kg.

Calves nurse below water, close to the surface. The mother glides in a horizontal position with her tail arched, and the calf swims on its side with its mouth on the right or left mammary gland. The mother’s milk is very rich so that the calf rapidly develops a thick, insulating layer of blubber. The milk fat content fluctuates as the calf develops, ranging from about 48% milk fat at the beginning of the nursing period and gradually decreasing to approximately 28% in the months that follow. A calf may nurse for 12 months or more. A calf may essentially be weaned at one year of age but may continue to nurse occasionally for several more months.

Orca photos, Rolf Hicker Nature Photography

Conservation Status & Comments

Center for Biological Diversity: Puget Sound killer whales external

No attack on a human by an orca has ever been recorded in the wild. Orcas are not yet regarded as an endangered species overall. In 1946, 14 countries formed the International Whaling Commission (IWC) external by signing the International Whaling Convention. The IWC set regulations of whaling to protect the future of whale stocks as a resource to humans.

Currently the IWC has no jurisdiction over dolphins such as orcas. However, now that the harvest of most large whales has stopped, the IWC has expressed an interest in playing a role in managing smaller cetaceans as well.

The Clownfish is surely everybody’s favourite fish? It may also be one of the cleverest. It is one of just a few fish that can make itself immune to a sea anemone’s sting.

Unlike other fish, the Clownfish is able to swim freely between the poisonous tentacles of an anemone without being stung. This gives them protection and is a very good reason to take up residence! In fact, most Clownfish spend their lives living in small groups within easy reach of ‘home’.

But what about breeding time? If they never stray far from home, how do they meet other Clownfish? The answer, of course, is stranger than fiction.

Clownfish communities usually consist of a breeding pair and a few non-reproductive, younger and smaller males. When the female dies the larger male changes sex and takes the place in the shoal as the female. This is because all clown fish are born male. This is known as being a protandrous hermaphrodite.

Clownfish lay their eggs in large batches on flat surfaces near to their host anemone, usually around the full moon. Depending on the species, this could be hundreds or thousands of eggs. The male parent will usually guard the eggs until they hatch about 6 to 10 days later. This usually happens about 2 hours after dusk. Once the eggs have hatched the male will usually stay to take care of the young until they reach sexual maturity.

Don’t be fooled by Hollywood though. The truth about them is that they are extremely territorial and aggressive fish and enjoy a very special entente cordiale with their host. Basically they help each other in their quest for survival. The Clownfish will eat the remains of fish paralysed and eaten by the anemone and, in return, keeps the anemone healthy by eating any rotten or damaged tentacles. The Clownfish will also feed on small, invertebrates that could harm the anemone whilst the Clownfish’s excrement will provide nutrients to the anemone. It’s a beautiful relationship!

Whenever a Clownfish takes up residence in a new anemone it performs an elaborate dance, during which it gently touches the tentacles with parts of its body. This could be the way the fish acclimatises itself with the anemone so it doesn’t feel the stings.

Clownfish live in the warmer waters of the Indian and Pacific oceans,

The whale is the largest and most majestic animal to ever inhabit our planet. Originally a land dwelling four-legged creature that returned to the waters we all evolved from millions of years ago, they now populate the earth’s oceans. The oceans once teemed with these wonderful mammals that, like us, breath oxygen, give birth to live offspring and have a complex family- and social structure. But their numbers were decimated by humans for profit and many whale species were driven to the brink of extinction and are still in grave danger of vanishing forever.

Despite an overwhelming majority vote amongst the Earth’s population to protect the whales, there are still some nations that kill them for money. Help stop this senseless killing. Learn and educate yourself with facts about whales and begin to understand this majestic animal and how it shares the world we reside in.

These mammals are particularly intelligent mammals and like humans, place much value on their families and the role that each member plays within the unit. Notably, the individual families also travel and migrate together in pods and each family member continues to play a vital role within that pod, as a greater unit of the family. These groups demonstrate the sociable nature of whales, and their unspoken cooperation with one another is evidence of the insight and sense of responsibility of the animals.

These mammals have always held a distinct fascination for human beings. Research and folklore meet on a platform of this intense interest in these magnificent animals, as has been confirmed by ageless tales that have survived the last few decades, even centuries. Whales have been used to signify love, grace and intelligence in culture and folk tales. However, whales also have significance in our unconscious dreams.

This article continues here.These mammals experience adolescence between their weaning and the time of their reaching sexual maturity. The actual ages at which these stages are achieved depend very much on the whales species in question. Baleen whales are weaned between eight and ten months of age, while toothed whales depend on mother’s milk for up to three years. Weaning means that these calves are no longer reliant on their mother’s nutrient-rich milk.

This article continues here.

Whales have long been esteemed by the human race. Their often-awesome scale is juxtaposed by their slow, quiet nature, and their irrefutable insight. Their means of communicating with one another and their demonstration of distinctly human characteristics continues to fascinate researchers as they delve further into these magnificent creatures and their psyche.

The common term “whales” often excludes the smaller species, such as porpoises and dolphins. However, the fact remains that these are, essentially, part of the cetacean family and should be included in the terminology. The largest animal ever to have lived, as far as scientific knowledge extends, is the Blue Whale, which reaches a length of just under 33 metres.

These mammals are split into two main categories; toothed and baleen. As their name would imply, toothed whales have a distinct set of teeth and include orcas, dolphins and the Sperm Whale. These animals feed on fish, squid and even larger mammals, such as seals (depending on their own size). Baleen whales have baleen plates that act as filters in their mouths, rather than teeth. They draw water and food into their mouths and then filter the food from the water by pushing it through their plates. The Blue and Humpback whales are excellent examples of baleen whales.

Whales are mammals and, therefore, have lungs rather than gills. They decide when to breathe, and come to the surface to do so through a blowhole on the top of their heads. They also surface to breach (lifting their bodies partially out of the water) and slap the water with their tails in impressive displays.

These mammals communicate with one another using whale songs, which often sound very high-pitched to the human ear. These songs are unique and fascinating when considered in more detail.

Unfortunately, these mammals have long been hunted for their valuable meat as well as their fat or oil, their baleen plates and even the ambergris of the Sperm Whale (used in the production of perfume). Whaling, particularly before regulations were passed in many places in the world, ensured that some species were almost completely decimated. In the 1900’s alone, over 2 million whales were slaughtered.

Many environmental organisations are working hard now to preserve and propagate the valuable whales we have remaining in waters all over the world.

 

What is Marine Ecology?

Marine Ecology is the scientific study of marine-life habitat, populations, and interactions among organisms and the surrounding environment including their abiotic (non-living physical and chemical factors that affect the ability of organisms to survive and reproduce) and biotic factors (living things or the materials that directly or indirectly affect an organism in its environment).

Marine ecology is a subset of the study of marine biology and includes observations at the biochemical, cellular, individual, and community levels as well as the study of marine ecosystems and the biosphere.

The study of marine ecology also includes the influence of geology, geography, meteorology, pedology, chemistry, and physics on marine environments. The impact of human activity such as medical research, development, agriculture, fisheries, and forestry is also studied under marine ecology. In some ways, marine ecology is more complex than the relatively straightforward study of a particular organism or environment because of the numerous interconnections, symbiotic relationships, and influence of many factors on a particular environment.

To understand the difference between marine biology and marine ecology, it may be useful to look at a community of organisms. A marine biologist may focus on behavioral relationships between the organisms in one particular species while someone studying ecology would study how the behavior of one organism influences another. An ecologist would also look at abiotic factors and how they influence that organism. A scientist studying community ecology might study a group of organisms to see how they influence other species and abiotic factors.

The major subcategories of ecology are:

  • Physiological ecology: the study of how biotic and abiotic factors act on the physiological characteristics of an organism and how the organism adapts to the abiotic and biotic environment.
  • Behavioral ecology: a subcategory of ecology that studies which ecological and evolutionary dynamics are responsible for the way in which organisms adapt to their environment.
  • Population ecology: the study of populations of organisms in a particular species and how the populations interact with their environment.
  • Community ecology: the study of how species react to each other in a community.
  • Landscape ecology: the study of how organisms interact with a particular landscape.
  • Ecosystem ecology: the study of how energy and matter flow through ecosystems.
  • Global ecology: the study of how energy and matter interact in the entire web of life on Earth.

The study of ecology in general includes all of the subcategories listed above as they apply to marine ecology, animal ecology, plant ecology, insect ecology, arctic ecology, tropical ecology and desert ecology.

What is needed to sustain life on Earth?

Earth has been divided by ecologists into four areas: the hydrosphere, the lithosphere, the atmosphere, and the biosphere. The hydrosphere refers to water on the planet, the lithosphere consists of soil and rocks, the atmosphere is the air, and the biosphere refers to all of the life on Earth. The biosphere can be visualized as a thin surface layer on the Earth from 11,000 external m below sea level to 15,000 external m above sea level, even though there are no permanent residents living in the atmosphere.

The Biosphere

The first life on Earth was formed in the photic zone of the hydrosphere when organisms with more than one cell evolved in the deep ocean benthic zones. After the ozone layer formed, which protects land organisms from harmful UV rays, life began to evolve on land. After the continents separated and reformed, biodiversity began to increase as life began to adapt to new environments. Biodiversity can be observed at the genetic level, the species level, the population level, and the ecological level.

Abiotic elements like carbon, nitrogen and oxygen are present in great quantities in the biosphere. Phosphorus, calcium, and potassium are also present in smaller amounts. All are elements critical to the existence of life. Every element in the ecosystem transforms from mineral to organic forms and back to minerals and is never destroyed. Life depends on energy from the sun and the organisms that are capable of transforming light into chemical energy form the basis for the food chain. The process of photosynthesis converts light into chemical energy, resulting in the production of glucose and oxygen. Other organisms depend on glucose produced by photosynthesis for energy to fuel biological processes such as cellular respiration. During cellular respiration, organisms split glucose back into water and carbon dioxide. The breaking down of glucose releases and utilizes energy from the sun stored by photosynthesizing plants. The oxygen level of the Earth’s atmosphere is largely reliant on the amount of photosynthetic activity and respiration going on in the biosphere. A build up of elements in areas with a lot of organisms is prevented by circulation of the atmosphere with global air currents.

The Earth is full of cycles simultaneously occurring and interlaced. Water is cycled through the hydrosphere, lithosphere, atmosphere, and biosphere in relatively predictable movements.

The flow of basic elements and the stability of the Earth’s climate and temperature depend on oceanic currents and the vast amount of water stored in the ocean. Ecologists often depend on computer modeling to determine how human activity can influence the intricate cycling of the biosphere.

Every organism is influenced somehow by every part of its environment. An ecosystem is any place or time where organisms interact with their environment. Ecosystems can be divided into the life in the area and the area in which life exists. Biocoenosis is the life in the area and the biotope is the environment by which life is influenced. One form of interaction in the ecosystem is the food chain, a system moving energy and matter through organisms and the environment. A microecosystem is a small system like a fish with parasites. A mesoecosystem could refer to the coral reef in which the fish lives and a macroecosystem might be the area in which the coral reefs are located and how they interact.

Abiotic factors include geographical, climatological and geological influences. Biotopes are determined by certain abiotic factors. Examples of abiotic factors include, water, air, soil, pH, salinity, temperature, amount of light, and even natural catastrophic events.

A grouping of populations of plant, animal, or microscopic organisms is referred to as a biocenose. When the number of organisms in a species becomes too small, inbreeding reduces the genetic diversity causing weakness in the species and possible extinction. The stability of a biocenose is also connected to biotic ecological interactions by organisms of the same species or organisms of different species.

Interactions between organisms of the same species are cooperation, competition, territorial divisions, and organization in the population. These factors are collectively referred to as intraspecific relations. The interaction of organisms of different species is referred to as interspecific relations and can include symbiotic interactions, competition, parasitism, and infectious disease. When two organisms occupy the same ecological niche, competition for resources can occur. It is important to determine whether the interaction is positive for both species, negative for both, or positive for only one species. Another example of an interspecific relation that is negative for one species and positive for the other is predation. Predatory activities form the basis for all food chains. While predation is natural and provides nourishment for the predatory species, in some cases it can upset the balance of the food chain when the prey species is already overexploited.

Biogeochemical cycles are present when minerals and organic materials are used by organisms and sent out as waste. Ecosystems can remain relatively stable when untouched by catastrophic events, detrimental human activities, or other unusual occurrences. Homeostasis, or self-regulation of ecosystems, occurs when supported by natural control mechanisms.

A biome is an ecological area separated from other areas by certain definitive characteristics and relies on the interdependent nature of ecosystems. Water, among other elements, can cycle from one ecosystem to another. Organisms like salmon and freshwater eels often move from one ecosystem to another. The biosphere includes all of the Earth’s biomes. An example of a biome is the photic portion of the ocean where sunlight is present and photosynthetic algae can be found. Biomes are divided into ecozones corresponding loosely with the continents and are further divided into ecoregions.

Species are related to each other through the role they play in the food chain as producers, consumers, and decomposers. Producers are photosynthesizing plants, consumers are herbivorous or carnivorous animals, and decomposers are organisms (such as bacteria) that break down organic material into minerals, which are eventually used by producers. There are more producers than consumers. The total amount of living matter in any place is called the biomass. When the biomass of plants increases it is measured as the primary productivity: the biomass produced by consumers and decomposers is measured as the secondary productivity.

Primary and secondary productivity are measurements used by scientists to determine an ecosystem’s capacity to support life.

An ecological crisis can take place when species or populations evolve in an unsustainable way. Sometimes the quality of the environment is lost after trauma, like a lack of rain or an increase in the temperature of a region. Other times, too much predation can ruin the balance of an ecosystem, as can be seen with overfishing by humans. Sometimes, too many organisms in one place will cause a poor living environment for others. There are different time scales for ecological crises ranging anywhere from a few months to millions of years. Extinction events can affect many species or just a few individual species. Human activities, like oil spills, can cause local crises as well as global crises like global warming. Even with a local crisis, the loss of a few species can have a disastrous effect on the survival of others in the food chain. A global crisis can result in a loss of nearly all species on Earth. The most common example of such a crisis is the extinction of the dinosaurs. Other examples of well-known ecological crises are the Permian-Triassic extinction event, the Cretaceous-Tertiary Event, Global Warming from the Greenhouse effect, the hole in the ozone layer, desertification and deforestation, and nuclear meltdowns like Chernobyl. Fortunately, nature always prevails and when species disappear, new species evolve.

Fewer corals, marine life hurt reefs
‘State of the Sanctuary’ report outlines human impacts
BY TIMOTHY O’HARA Citizen Staff
tohara@keysnews.com

Reduced numbers of coral colonies, increasing prevalence of coral diseases and low abundance of key fish species such as grouper are among a series of problems outlined in a comprehensive report on the state of the Florida Keys National Marine Sanctuary.

Sanctuary managers on Wednesday released the “Condition Report 2011 for Florida Keys National Marine Sanctuary,” the first report since the sanctuary was established in 1990 that outlines the health of the coral reef ecosystem and the fisheries in sanctuary waters.

It describes the status and trends of the sanctuary’s water quality, habitats and marine and cultural resources, and the human activities that affect them. The report cites a multitude of threats facing the sanctuary, from ocean acidification to illegal artificial lobster habitat, commonly called condos or casitas.

The report is one of an ongoing series of such reports for 13 national marine sanctuaries and the Papahnaumokukea Marine National Monument in Hawaii.

The report comes as the sanctuary has begun to discuss tweaking its regulations, which could lead to more rules and new or expanded no-fishing areas. It will guide the review of current sanctuary regulations and management policies, which is scheduled to begin in 2012. The report also will provide an important baseline on the status of sanctuary marine resources, Sanctuary Superintendent Sean Morton said.

“This will steer future regulation,” Morton said. “This is the bedrock for the work that will be done. … Regulations will address additional needs for protection.”

The report documents improvements in local water quality, as many Keys communities are converting to advanced wastewater systems. It also shows increases in the size and abundance of some fish species and Florida spiny lobster in large reserves within the sanctuary.

Also documented are many of the ongoing problems that could make full recovery impossible for elkhorn and staghorn coral, queen conch, goliath grouper and other species that have seen sharp population declines in the past 20 to 30 years.

The report finds a reduced number of corals, queen conch, long-spined seas urchins, groupers and sea turtles. A “reduced abundance of selected keystone species has caused or is likely to cause severe declines in ecosystem integrity,” the report states. It also says the species are at such “severely reduced levels” that “recovery is unlikely.”

The sanctuary needs to reconfigure its no-fishing and protected zones to better protect snapper and other fish spawning populations, marine conservationist and former commercial spear fisherman Don DeMaria said. Some of the protected areas are covering the wrong areas and are not helping fish repopulate, he said.

Biodiversity of coral and fish species is also in decline, according to the report.

“Relative abundance across the spectrum of species has been substantially altered, with the most significant being large reef-building corals, large-bodied fish, sea turtles and many invertebrates, including the long-spine urchin,” the report states. “Recovery is questionable.”

Significant coral bleaching and disease has caused substantial declines in coral cover over the past two decades, the report states. Coral cover has dropped to a point where there is less than 10 percent of living coral along the main reef tract and closer to shore and about 25 percent live cover on deeper reefs and patch reefs, according to some estimates.

Coral diseases usually coincide with bleaching, as bleaching weakens coral immune systems and makes them more prone to disease, said marine biologist Mark Chiappone, who has conducted field work on Keys’ reefs for more than 20 years and peer-reviewed the report. One disease in particular, called white band disease, has been significantly deadly. The disease wiped out 80 to 90 percent of elkhorn and staghorn coral — the Keys’ main reef-building corals — in the Caribbean in the 1980s and 1990s.

“That changed the face of many reefs,” Chiappone said.

Coral disease and death is tied to pollution and water quality. A recently released report identified human sewage as the source of a pathogen that causes the potentially fatal white pox disease. A research team from two universities took samples from Carysfort Reef off Key Largo, Sombrero Reef off Marathon and Rock and Sand keys off Key West. All of the reefs tested positive for the pathogen found in human sewage, said University of Georgia ecology professor and study author James W. Porter.

Traps, careless divers and other human activities have played a role in coral decline at a local level. On a larger scale, reefs are being impacted by rising sea temperatures and greater ocean acidification.

“It’s like death by a thousand cuts,” Chiappone said.

Coral decline leveled off in 1997, but no new coral recruitment has occurred and not much recovery has occurred in the past 14 years, the report says. Many of the areas that were once rich with coral are now covered in algae, as one of the main reef grazers, spiny urchins, experienced a massive die-off in 1983. Urchins generally clear areas of algae, which help coral recruitment.

To combat human impacts, the sanctuary has implemented both charter dive boat and dolphin watching education programs for local operators, which reward them for conservation efforts. The sanctuary is working with marine biologist Ken Nedimyer, who is rearing coral in an offshore nursery. The corals are used for research and to replace coral colonies damaged in vessel groundings.

The Sanctuary Advisory Council will meet Tuesday in Ocean Reef to discuss the time frame and the process for implementing rule changes, which could set up new closed areas, put in place more protections for coral and fish species and establish a mandatory boater education rule. National Marine Sanctuaries Program Director Don Basta will attend.


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