LECTURE SIX OF ELEVEN

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1 LECTURE SIX OF ELEVEN There are many other products like shark skin which can be used as sand paper because of its rough surface. Mammals have also supplied non food items. Whales have supplied oil, baleen and ivory. Otters and seals supply furs. Gathering resources from the sea is quite old. Archaeologists have found evidence of fishing going back as far as 42,000 years ago. Recently, a site in East Timur, a maritime state in Southeast Asia was excavated with fish hooks. This alone is not significant as there are sites in Africa with fishing equipment and fish bones, but these are fresh water fish. The site at East Timur has fish bones from salt water fish - and more importantly they are bones from pelagic (deep water fish). This implies that the people had the ability to travel into water over the continental shelf. In addition, the bones are from among other things, tuna a rather fast moving fish which is unlikely to have been speared or harpooned.(spears and harpoons differ in that harpoons are barbed) The fish hooks found are not large enough to have been used to catch tuna and so the method of catching the fish remains unknown. Nets are possible however.

2 The evolution of technology is largely examined anthropologically on the land. Early anthropologists were involved with a Zeitgeist a spirit of the times which was evolutionary. The middle of the 1800 s saw a rise in the idea of evolution. Lyell had postulated geological evolution, Darwin was dealing in biological evolution. The early sociologists and anthropologists followed suit. They saw an evolutionary development in technology. Basically technological evolution assumes that people can accomplish the same amount of work using less human energy or more work with the same amount. The development shows for example the development of adl-adls or throwing sticks to bows and arrows. Throwing sticks increase

3 the length of the arm and hence the speed of the missile thrown. A bow and arrow stores the pull off the arm in the bend in the wood which is released immediately. Similarly the way food is gotten shows an increase of sorts. Social scientists see the earliest form of food getting as being Hunting and Gathering. From there people start to do horticulture a planting of food but without a plow Finally, they move to agriculture, where a plow is used. These levels were classified as savagery, barbarism and civilized. Note the lack of maritime food supply in the list. Perhaps this is because anthropologists come out of non-maritime cultures by and large. One could think about evolutionary movement from fishing with a hook or spear in which one fish is taken at a time moving on to nets and weirs where several or more fish are taken at a time to something like fish farming. In some instances traps and pots are used to catch forms which tend to crawl or are not easily caught by hooks and the like Both the agricultural and maritime routes are potentially capped by the development of commercial farming and fishing. Commercial fisheries take enormous nuber of fish at a time using different kinds of nets: Gill nets in which the spaces in the net are of a specific size so that smaller fish can pass through. Larger fish swim in, but cannot pass through and they fish cannot back up because their gills become caught against the lines. A second kind purse seine nets encircle a school of fish and then the net can be closed like a purse. The third kind are trawls in which the net is dragged through the water or along the bottom.

4 Finally there are long lines. These are basically lines that stretch out behind the boat with many hooks. They may be floating on the surface or weighted to be closer to the bottom. This allows some selection of the kind of fish since they live at different levels. When commercial fishing arrives on the scene, large numbers of fish are taken. Generally, commercial fisheries are after a specific kind of fish. Unfortunately, it is impossible to catch only one type of fish in a net or on a long line. The result is that some fish are caught which are not wanted. These are known as by catch and are often just thrown back since they are no longer alive. Once a fishing industry begins to develop i.e. one which is after a specific kind of fish, there are many fish and so the profits are high. Fishermen tend to go for the larger fish of the group so that they can maximize their profits. It is more efficient to catch one 5 pound fish, than five 1 pound fish, but the amount gotten remains the same. So initially, 2 things happen. As a new industry opens, it will attract more and more fishermen. Unfortunately, this produces a problem since these are the more mature fish. As a result, the breeding population begins to fall off. This is known as recruitment overfishing Recruitment overfishing: Recruitment overfishing occurs when the mature adult population (spawning biomass) is depleted to a level where it no longer has the reproductive capacity to replenish itself there are not enough adults to produce offspring. Another kind of overfishing called growth overfishing Growth overfishing: Growth overfishing occurs when fish are taken too small, before the fish have grown to a size that produce the maximum yield.

5 This reduces the value of the catch since if the fish were to grow, the individual fish would weigh more and bring a higher price in the market. Overfishing occurs when many fishermen become attracted to the same new fishing industry. As a result many people move in to take the fish. The numbers start to decline. Best option: stop fishing for that fish. Does it happen? No. Studies show that within 15 years of a new fishery opening about 80% of the largest fish are taken. A number of fishing industries have collapsed over the years. The anchovy industry in Peru collapsed in part because of overfishing, although there were additional problems caused by El Niño about which we will have more to say later. Another industry which collapsed was the cod fishing industry in New England and Canada. Cod were reported on the Great banks as being so numerous one could walk across their backs. Overfishing and poor fisheries management have been blamed Finally the industry put restrictions on how much cod could be taken by any vessel. This however made problems since a vessel would have to stop fishing altogether as soon as it took the quota allowed by the government. Since people caught cod as by catch they could reach the limit and would therefore have to stop fishing altogether since if they caught a cod as a by catch, they would have exceeded the limit. As a result of the ban, it is estimated that 40,000 people out of work. The fishery shows some small signs of recovery.

6 Blue crab larvae are part of the Bay s planktonic community, serving as food for menhaden, oysters and other filter feeders. Juvenile and adult blue crabs serve as food for fish, birds and even other blue crabs. Striped bass, red drum, catfish and some sharks depend on blue crabs as part of their diet. Soft shell crabs that have just molted are particularly vulnerable to predators. Blue crabs are among the top consumers of bottom-dwelling organisms, or benthos. Opportunistic feeders, they eat thinshelled bivalves, smaller crustaceans, freshly dead fish, plant and animal detritus, and almost anything else they can find. Because blue crabs feed on marsh periwinkles, they help regulate periwinkle populations. Scientists are concerned that a drop in blue crab populations could harm salt marsh habitat, as periwinkle populations rise and the snails overfeed on marshgrass. Blue crabs also support a large recreational fishery in the Bay, and are the estuary's highest-valued commercial fishery. Over the past 60 years, blue crabs have dominated Chesapeake Bay fisheries, with an estimated one-third of the nation s blue crab catch coming The Blue Crab in Chesapeake Bay has also undergone a decline See: Whales are endangered as a result of over hunting. Whalers are found in many cultures from Europe (Scandinavian), Canadian, US, Japan, St. Vincent, the Nootka on the NW Coast.

7 Whaling nations formed the International Whaling Commission in 1946 to protect the rapidly dwindling whaling stock. In effect, they were attempting to protect their natural resource. Since then a number of nations have joined (now 89) many of which are small non whaling nations whose membership fees are paid by anti-whaling groups. The IWC distinguishes three kinds of whaling aboriginal, commercial and scientific. Aboriginal whaling and scientific whaling are still allowed whereas commercial whaling is forbidden. One of their initial moved was to protect the endangered Blue whale by outlawing the taking of the whales. As a result, Blue whale populations began to increase. In the 1800s the whales were hunted by the US largely for the very fine oil found in the whales and also for baleen. Other countries, like Japan, Iceland, Inuit, Nootka and the like took whales for food. Japan has a saying A single whale can feed seven villages. The Japanese have been whaling since pre contact with the west. The whaling was in some parts organized by a military leader who organized the hunt along similar lines. A look out point was found from which signals could be sent to a relay station when a whale was sighted. From there the whalers in the towns were notified. Many people from very young to very old were involved in the hunt since nets were used which had barrels fasten to them. After the whale was taken the older and younger people went and gathered up the barrels and nets. Each person got a percentage of the whale if they had been involved in the hunt. The look-outs would report information about the whales. Female whales with calves were not hunted, in a kind of parallel with concerns about stocks with the abalone divers. When WWII broke out the Japanese whaling industry came to a halt when the whaling ships were converted into military vessels.

8 At the end of the war, Japan was short food and the American government suggested that the Japanese return to whaling to get food. Some years later, when the IWC was putting in place the whaling ban, the US suggested that the whale ships be converted to transport (among some other things) to Japan. Unfortunately, Japanese had a problem with that. A highly stratified society, Japan had an untouchable caste called the Eta, who were people who dealt with deceased animals. After the war the US written Japanese constitution, made illegal discrimination against the Eta. During the war some had passed as non Eta by having moved around Japan. Others had decided to assert themselves and as a result, the Japanese government decided that only Eta could handle deceased animals. As a result, any job (like shipping meat) became something for Eta. Since the number of Eta interested in this job was too small to make it work, the idea had to be scrapped. Japanese had stopped commercial whaling but did some scientific whaling. This led to questions as to what was happening to the whales after the research was completed and the anti-whaling nations (known as like minded nations ) argued that the Japanese whale meat from the scientific whaling was being sold. The Japanese did not want to throw the meat away and sold some as a way to raise money for the scientific whaling. In a sense, this is how some countries deal with trophy hunting. Licenses are issued for a lot of money, which allow hunters to take a small number of animals, the money from which is used to arrange for protection for the larger number of animals. The Pacific Gray Whale and the Atlantic Right whale were two of the most endangered whales around. The Pacific Gray whale was close to extinction as a result of its being hunted by the US for

9 dog food. The right whale was so named because it floated when it was killed and therefore was the right whale to take. The Atlantic right whale remains the most endangered of the whales. Legislation requires ships slow down in areas where they are found and a distance must be maintained between the vessels and the animal. The IWC has now put a moratorium on all whaling with the exception of scientific whaling (whales take for the purposes of scientific research) and aboriginal whaling although the definition of aboriginal in unclear, although the idea is that the whale meat cannot enter the commercial market. This is tricky with cultures like Japan where the Japanese are aboriginal but the culture is commercial. The Japanese can sell whale meat as food from whales that have been taken for scientific whaling although this is seen as improper by many non whaling member nations. The Japanese had in the past been appalled by American whalers who took whales for the oil, blubber and baleen and then dumped the meat back into the ocean. The Makah Indians in Washington State have a treaty which allows them to take one whale a year. They voluntarily stopped when it was held that the Pacific Gray whale which they took, was endangered. When then whale stock recovered, they decided to take a whale a year. At that point, anti whaling people shot up signs on the reservation and the US made no protest of a Canadian ship which came into Puget Sound where the Makah were going to take the whale. William Lloyd tragedy of the commons. No single fisherman owns a defined part of the fishery. Instead it belongs to society as a whole res nullus a common resource. Therefore an unequal disposition of rewards and punishments develops. An individual

10 fisherman who continues to fish knowing the population is declining still receives rewards for catching the fish. Negative result smaller population to be fished in the future. So the idea is keep fishing and industry collapses. With land consider Plymouth and the Mayflower travelers. Initially, all the crops were shared among the population. So several people stopped working but still got rewarded with everyone else. The next year Plymouth colony gave that up. Pollack and Mackeral overfished. They are food for sea lions (down 79%). Sea lions are food for killer whales now turning to the endangered. sea otters as food. Sea otters eat sea urchins which control the growth of kelp. When the sea otter population drops, the sea urchins go uncontrolled and over eat the kelp, killing off too much of the kelp. This destroys the habitat for many animals that use the kelp (like estuaries) as protection for young. So the overfishing leads not only to serious changes in the relationships between tropic levels but also the environment. Darwin s theory of evolution talks about the way organisms fit into their ecological niches. The niche is not just the non living environment but also the other organisms there. The Darwin theory involves a few steps: (a) (b) (c) (d) There is a limited amount of food and so there are limited numbers of organism that can be supported. There is natural variation in the population individual organisms in the same species exhibit some differences in different areas. Natural selection in which some of the variants allow some animals a better chance to survive Survival of the fit (there is a better chance for some of the organisms to pass their genes on to their offspring)

11 Initially the Darwin theory thought that the variation was caused by organisms passing certain traits they had acquired on to their offspring. Later, genetics was substituted for the Lamarkian ideas One of the difficulties is that humans can have an effect on the other populations. The problems of overfishing (and over hunting) have impacted numerous species and ecological areas. In some cases, like those above, animal populations have been reduced or lost completely. In others, they have caused increases in population. The ban on hunting seals, for example, caused a increase in the number of seals. Seals eat 6% - 8% of their body weight in fish daily. Fisherman have noticed serious declines in some fish recently which may be caused by this In addition, an increase in the number of shark attacks by adolescent Great White Sharks around Cape Cod may be caused by the increase in the seal population since adolescent sharks change their diets from fish to seals and have to learn how to hunt them. While they are learning, they seem to mistake people swimming in the water for seals. So in this case, protecting seal populations may have led to the increase in shark attacks on people. Similar problems have arisen in places where there are conflicts between groups that are pro-bear and others that are pro-fish. Both are endangered. Some people who were pro fish want to continue a law that allows people to hunt bears. That will keep the population of bears down which will allow the fish to increase in numbers. The pro bear people want to ban bear hunting so the bears can increase more quickly in numbers. Some people have wondered what gives people the power to decide which species survive and which don t. In any problem with decreasing populations, there are questions about what will allow the species to increase. Some of the factors

12 are the gestation period of the organisms, the number of organisms left, the amount of food available and so on Not only do human populations impact organisms, but many nonhuman factors do as well. Volcanic eruptions spew greenhouse gasses into the atmosphere, algal blooms can impact other organisms. Impacts from space can do the same.