CLIMATE CHANGE EFFECTS ON OCEAN ANIMALS G. SELVAMANGAI Research Scholar Herbal & Phytochemical Department Biozone Research Pvt limited

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1 CLIMATE CHANGE EFFECTS ON OCEAN ANIMALS G. SELVAMANGAI Research Scholar Herbal & Phytochemical Department Biozone Research Pvt limited Today we are going to discuss on some ocean based animals and its effects on climatic changes. The poster child for global warming is the polar bear, sea turtles, right whales, penguins, seals, lobsters and cod. We are going to discuss in detail for each of these animals. First we are going to discuss on polar bear. What is the effect of reduced sea ice on polar bear? The Arctic s top predator, the polar bear, is affected both by the reduction in sea ice and by reduced stocks of its primary food, the ringed seal. Polar bears use sea ice as a platform for hunting their prey and for resting. They catch adult seals when they come up through holes in the sea ice and search out the snow covered ice caves of seal pups. But sea ice is decreasing throughout the Arctic race due to climatic change. So automatically the ice reduction decreases the abundant of seals and increases the amount of energy and time needed for hunting leaving less energy for preproduction. Rising temperatures mean that large areas of the ocean that were once frozen throughout the year have become open water. Polar bears often have to swim between long areas of stable ice. AS sea ice becomes thinner and multi-year ice disappears, a greater proportion of females make their dens on land, expending more energy to get there. Decreases in the physical condition of females and in reproduction have already been documented. So this is the image taken during a NOAA expedition. In 2008, the US fish and wildlife service listed the polar bear as a threatened species under the endangered species act. The nation s primary tools for conserving imperil plants and animals. A threatened species is defined as slightly

2 to become endangered in the foreseeable future. This is an image from USGS expedition. Next we are going to discuss on sea turtles. How are these sea turtles affected by climate change? Rising temperatures, rising sea levels and other trends are having an effect on the world s sea turtles. Six sea turtles are already on the endangered species list green turtles, hawksbills, loggerheads, kemp s ridleys, Olive ridleys and leatherbacks. All female turtles come ashore at nesting beaches, dig nests in the sand, lay their eggs and then return to the sea. Erosion of nesting beaches caused by rising sea level and more intense storms adds the potential to further dangers to nesting beaches where the dogs, rat, rat holes already prey on the eggs of marine turtles. So this climate change directly affects the reproduction rates of these turtles. Apart from this firstly the sea level when it raises significantly it results in the nesting beach area on the low level sand regions such as the bonile, Maldives and the Great Barine Reef. Second rising temperature increases the chance and sand temperature will exceed the upper limit for egg incubation with 34 degree Celsius. Third, rising temperatures bias the sex ration toward the females because temperature during incubation determines the sex of the egg. Loggerhead turtle nests in Florida are already producing 90 percent females owing to high temperatures, and if warming raises temperatures by an additional 1 degree C or more, no males will be produced there. So this is a picture taken by New England Aquarium Educator Jessica Lavash in Padre Island, Texas. Adult feeding patterns are also affected by climate change. Sea grass buds are in decline. Water temperature is higher on inter-tidal sea grass flags and coral reefs typically feeding browns for green turtles are affected by bleaching. So all these will have a drastic effect on the reproduction rate of the sea turtles. Sea turtles have existed for more than 100 million years and have survived ice ages, sea level fluctuations of more than 100 meters and major changes to the continents and the seas. As a result, they may

3 be able to respond to unfavorable nesting temperatures or inundation of beaches as they have in the past, by seeking out new nesting sites or modifying the seasonality of nesting. It may however take decades of centuries for sea turtles to re-establish and stabilize their habitats and steadily encroaching human development of coastal areas makes the availability of due habitats for them very limited. This is an example of Kiwi, a kemp s ridley sea turtle. It was rescued and rehabilitated with the help of the aquarium in New England. So all this time we saw about sea turtles. Now we are going to discuss on whales. We are going to see how right whales are affected by climate change. It is long been recognized that humans have been brought the right whale to the brink of extinction through whaling and commercial fishing activities. There may be other human activity that could have even greater impacts on the remaining whales; human induced global warming. The key is a tiny Crustacean, Calanus finmarchicus, a key food source for right whales, as well as for cod, haddock, herring and mackerel. Without dense patches of this zooplankton, female whales can t bulk up to prepare for calving, carry a pregnancy to term or produce enough milk. When the concentration of the zooplankton is too low right whales do not feed. Such highly concentrated patches often occur when current converges at the boundary of your water of different densities. Changes of water temperature wins and water currents can affect patch formation of zooplankton. This is a picture of the whale. So we are going to discuss on a case study produced by NAO. Over 50 years of observation, scientists have learned that zooplankton is abundant when the North Atlantic Oscillation (NAO) Index which charts variations in atmospheric pressure centers over the North Atlantic is predominantly positive. When it becomes negative, the numbers decline. Right whales illustrate the dramatic downstream significance of NAO conditions. In the winter of 1996, the NAO index

4 exhibited its largest drop of the century. This atmospheric phenomenon has dramatic effect on the great ocean conveyor belt. So the latest slides we ll be discussing on what is a conveyor belt too, because conveyor belt also plays a very vital role in climatic change and its effect on oceans. The mixing of the warm salty water that moves north with the Gulf Stream and the cold less salty water moving from south from the Labrador Sea. Resulting changes in the water in the North West Atlantic determines zooplanktons ecology. The big drop occurred in 1998; it took two years before the 1996 drop in the NAO index had its effects on the zooplankton population downstream in the gulf of Maine, where it dropped tenfold. By 1999 the zooplankton numbers were climbing back up again. However, because of the right whales long reproductive cycle, the consequences of this climatic event were not over yet for the whales. in 1999 only one right whale calf was born. The lowest on record that were 21 in But in 2001, two years after the abundance of the zooplankton increased 30 right whale calf s were born. The most recorded since So this case study itself shows us very clearly that zooplankton had played a very vital role for the conservation of the whales. Hence all this ecological effects will have a drastic role on the mammalian animals prevalent in the ocean. Some scientists suggest that increased climate variability or a prolonged period of negative NAO index, which are both expected under a global scenario, would undermine the already tenuous recovery of the North Atlantic whale. So all this time we have been discussing on the effect of climate change on the survival of the right whales. Now we are going to discuss on another important and interesting one namely penguins. Penguins also have a greater role considering the ecology. Now kindly look at this picture. It depicts a penguin which is affected the global climatic changes. Now this temperature fluctuations leads to a severe decline in rock hopper penguins, emperor penguins, adelie penguins as well as the albatrosses

5 and the seals. All of these species are primarily squid eaters, eating krill and fish to a lesser extent. The reason for the decrease is not known, but declines in sea ice and a consequent decline in krill are likely. There was also a dramatic decline in penguins in Antarctica probably caused by disappearing sea ice over the past century. Adelie and emperor penguins which are dependent on sea ice have declined from 300 breeding pairs to 9 in the western Antarctica peninsular with a decline of 50 % in Terry Adely. Adelie penguins have declined by 70% of Andwards Island along the Antarctica peninsula. But or thriving it more southerly Ross island. Conversely, open-ocean feeding penguins, the chinstrap and the gentoo, haven t taken advantage of the ice s retreat, invading southward along the Antarctic Peninsula. Many penguins have survived severe climate change during the last 3 million years, showing the resilience of the species. Adelie penguins and chinstrap penguins. For example, have founded or deserted colonies on different parts of the Antarctic coast at various times during the past 5,000 years in response to changes in the amount of sea-ice and the amount of ice free land. Many penguins nested at Terenova bay on southern Victoria Land coast between 3000 and 4900 years ago than today because the weather was warmer and the bay less ice bound. These species may not go extinct as other locations for feeding and breeding could become available. Nevertheless, the temperature-related change they face certainly confers risk. The issue now may be about the rapid pace of the climate changes, possibly coming faster than the birds can adapt. Ok all this time we have been discussing on how the different oceanic environmental dependant species will be affected by the change in climate and next we are going to discuss on the seals. How have seals been affected by drastic climate change. According to scientists, the retreat of sea ice has reduced the platform that seals traditionally use to rest between searches for fish and mussels. The warming climate is changing the ocean s ecology to such a degree

6 that the survival of seals and their young has increasingly become a concern for marine biologists. The loss of sea ice in Antarctica has caused a decrease in the amount of algae, plankton and krill, the foundation of the ocean s food chain. This is a picture of the harp seal sighted in Boston s inner harbor. In recent years scientists have deducted their attention to the impact of climate change in the Bering Sea ecosystem which appears to be showing yearly climate change effects including the reduction of food for bottom dwelling creatures. A recent study shows that global warming will greatly affect the Bering Sea phytoplankton. Any changes affecting this ecosystem of crucial importance as the Bering Sea produces half of the fish caught in the United States and almost are the third world-wide every year. The Bering Sea has typically had a large presence of phytoplankton. Phytoplanktons are eaten by zooplanktons which are in turn eaten by large fishes. So it s like a food chain. Each one is inter-dependant. These changes observed in the Bering Sea ecosystem affects the marine mammals including seals that are part of its food chain. Now we are going to discuss on the effect of climatic change on lobsters. That is the impact of warmer waters on lobsters. As all of us know lobsters are coldblooded, their body temperatures determined by the water in which they live. Higher temperatures cause cold-blooded animals to use more energy for respiration, leaving less energy for feeding, growth, energy storage, immune response and reproduction. Much of a lobster s life is related to the temperature on the ocean floor what it eats, how successfully it breeds, where it migrates, etc. now this is a picture of one of the lobsters in the New England Aquarium. As the ocean temperature fluctuates so do the lobster s habits. Lobsters can respond to temperature changes by changing their habitat. For example, lobsters are likely to move towards high latitudes or to areas cooled by tidal mixing. Warming temperatures increase the lobster s respiration rate and oxygen needs while reducing the amount of dissolved oxygen available. Research has found

7 that as water temperatures rise above 69 degrees F, lobsters respiration rate increases to a point where their demand for oxygen exceeds the supply, causing physiological stress. Automatically leading to the decrease in the reproduction rate. Scientists have already seen the evidence linking raising sea water temperature to the spread of lobster shell disease in waters. It is actually caused by a bacterial infection and lobsters shell disease is dramatically become very common recent years. A new type of shell disease was observed in New England in the late 1990s when temperatures were higher than in previous years and has been steadily moving northward toward Maine and Canada. The incidence of shell disease is strongly related to the number of days during which water temperatures exceed 20 degrees C that is 68 degree F. the mechanism by which higher temperatures increase shell disease is not yet known. Actually it s under research and it may increase the rate of growth of bacteria suspected to cause the disease. It also affects the lobster s rate of growth no wonder so that they attain sexual maturity more quickly. In contrast to males which molt every year, mature females do not molt during the year they carry eggs, and only molt every two years. This long period provides more time for bacteria to infect females shells and higher sea temperature accelerates the rate at which they attain this vulnerable state. Next we are going to discuss on cods. Now commercial fish and shellfish including cod and lobster, have thresholds of water temperature that limit the conditions under which they can reproduce and grow. Temperature influences the location and timing of spawning, which affects the growth and survival of young cods. Now this is a picture of the cod taken in an aquarium and this is a map which depicts the habitats of cod s distribution in a world range. Now cods are generally found in temperate climes ranging from the shallows near the shore to deeper waters near the continental shelf. The habitat stretches from Greenland to north California like what we saw in the map off the coast of

8 Iceland and along the coast of Europe from the bay of Biskane to the Barren Sea which is the most important feeding area. The effects of rising temperatures on cod, for example, may be significant. Currently, temperatures in our waters are at the top of cod s favored range. If, under the IPCC high emissions scenario, the maximum temperature for cod is reached, this species could disappear from the waters south of Cape Cod. Off Georges Bank, cod could be vulnerable to loss of habitat. The gulf of Maine, north from Georges Bank is likely to continue to support adult cod throughout the century but not juvenile cod. Atlantic cod has been a staple of the New England fish industry since English sea captains name Cape Cod for their plentiful catch. Despite decreased yields due primarily to overfishing in recent areas. Massachusetts is still the top cod producing state with fish coming from the Georges Bank and the Gulf of Maine. The aquarium is working to help maintain the species stocked by being engaged in research to improve cods survival rates after being released. Generally phases of low production have corresponded with periods of high water temperature and other factors. So again we see marine species namely cod also has a drastic effect on its reproduction rate and the survival rate based on the climate. Now all this time we were seeing like how different mammalian species are affected by the change in climatic conditions. Ok. Now what is the tool for conservation? Ok first one is like all of of us have to have social responsibility. Where we say save Mother Nature. I mean to say like as human beings we should also play a very vital role in conservation of this mammalian species. And apart from this government are funding lot of projects in support of this research projects pertaining to the mammalian animals. And so like young people should take up projects in all these areas so as to support these mammalian species. Besides this in course of this project we use information systems like geographic information technology in which we will be able to identify or we will be able to monitor the movement of these animals. So we can adopt these kind of technologies and find out where these animals go and what is their adaptation strategy in the place they live in. so

9 as to develop our research focus. Further there are different policies, rules and regulations framed by the government for the marine conservation. So although there are lots of marine conservation action funds, as a human being we also have to take certain responsibilities. Take for example, the olive ridley turtles which are found on the coast of Tamil Nadu and Orissa. What happens is these turtles they come to the land for nesting. Now what happens is these turtles when they come to the land, they get caught in the trolleys net. And apart from this they also get attracted towards the lines on the beaches and they get misleaded and they go towards the land area and automatically this kind of turtles gets reduced in their rates. If we take marina, the second largest urban beach in the world, lot of initiatives are taken by the combined action of the government and the public to clean up the lands. I mean to say totally plastic is banned in those areas. So people are also coming forward for the contribution of the conservation of the mammalian species. And besides what happens is these mammalian species they get caught in the fishing methodologies what we follow. Boating methodologies, fish catching methodologies should also be considered because there are also lots of mechanized methodologies in which these fishes get caught and ultimately it leads to the reduction in the particular species of that fish. Besides that there are lot of exotic species of sharks which are eaten up in countries like China and Japan. So what happens is ultimately those species will come to extinct at one point of time. Government as well as public should also take some initiative for safe eating of sea food animals. And what happens ultimately this affects the entire ecosystems. We are not only concentrating on the effect of climate on ocean animals, besides that the entire ecosystem gets affected. Once these sea mammalians they get affected they have a drastic impact on the survival of the community which is dependent on solely on this sea based animals. Now we are going to summarize all our discussion. So today we discussed on the climate change effects on ocean animals in which we highly concentrated on

10 the sea turtles, right whales, penguins, seals, lobsters and cods. So if we see about polar bears we see that these bears use only sea ice is a platform for hunting their prey and for resting. So it is very important from our point from our side that we preserve this very important species by not increasing the global warming temperatures. Then we discussed about sea turtles and how are they affected by the rising temperatures and the rising sea levels and the other trends which have a very drastic effect on the sea turtles sex ratio. Apart from that we discussed on penguins. We know all of these species are primarily squid eaters, eating krill s and fish and the reason although we do not have the exact reason for their decline but research shows that the decrease in sea ice contributes drastically for the decline in the numbers of the penguins. Then we discussed on the lobsters and we saw as the ocean temperature fluctuates so do the lobster s habitats also. And why because these lobsters can respond to temperature changes by changing their habitats very frequently. These lobsters generally they are highly moving animals they keep moving towards higher latitudes or to the areas cooled by tidal mixing. Next we discussed on the tools for conservation of all these mammals. Then we discussed on how seals being affected by climatic change. We saw that this warming climate is changing the oceans ecology drastically to such a degree that the survival of the seals and youngs is increasingly become a very major concern for marine biologists thank you.