By Janelle Myers, Bob Daniels, and Tiffini Brookens

Northern Right Whales (Eubalaena glacialis)

The northern right whale is the world’s most endangered large whale. Its largest known population, about 300 animals, occurs in the western North Atlantic Ocean along the east coasts of the United States and Canada. A second population occurs in the western North Pacific Ocean in the Okhotsk Sea. Sightings from that area are too infrequent to develop a reliable abundance estimate. Right whale populations occurred historically in the eastern North Atlantic and eastern North Pacific Oceans, but recent sightings are so rare that it is doubtful that viable populations remain in those areas.

All northern right whale populations were severely depleted by commercial whaling and were commercially extinct by the end of the nineteenth century. By the 1930’s, surviving populations were reduced to the brink of biological extinction. The League of Nations first took action in 1935. Despite this ban, whales continued to be killed. The whales were hunted by whalers whose national governments were slow to sign the treaty, others were taken under provisions authorizing scientific research, and still others were killed by illegal whaling until at least the mid 1960's. The International Whaling Commission continued protection in 1946. The species is also protected under several Canadian Laws and as well as the Convention on International Trade and Endangered Species. The Marine Mammal Protection Act of 1972 and the Endangered Species Act in 1973 strengthened the protection. In 1986, the North Atlantic Right Whale Consortium formed. This organization funded by Congress, sponsors research through several institutions on the right whale. In 1988, the National Marine Fisheries Service (NMFS) first initiated recovery efforts for the right whale. Their responsibility to develop and implement recovery plans for federally listed marine species has resulted in several recovery publications and laws. They have determined that the threat most detrimental to right whales continues to be human beings. In light of this, the NMFS has created very strict guidelines effective as of March 17, 1997. These guidelines are for the purpose of reducing the possibility for vessel interaction and injury to the right whale as well as any disturbance to their behavior. Though efforts are many, the future of the right whale is still unsure. Currently, whaling is not considered a direct threat to the species. However the remaining populations are now so small that other human-related impacts, particularly entanglement in fishing gear and ship collisions, threaten their recovery. Right whales are vulnerable to ship collisions because of their behavior. Behaviors such as logging (resting quietly at the surface), skim feeding, nursing, mating at the surface, and preference for coastal waters where there is more ship traffic make them prime targets. Calves also have limited diving ability and spend most of their time at the surface. The right whales seem oblivious to ships while engaged in the preceding behaviors. It is estimated from photographs that 60% of the population has been affected by a gillnet or the lines of a lobster trap. Of all confirmed deaths since 1970, 40% are attributable to human factors.

Reasons for whaling the northern right whale: has commercially valuable products, a slow swimming speed, the attribute of floating when dead, and a generally coastal distribution.

The right whale has the smallest total population of all the great whales except for the Bowhead whale. The conservation of Baleen whales is essential because of their uniqueness. They have evolved special double blowholes and symmetrical skulls in their growth to enormous sizes. Even if the human threat were completely eliminated recovery for the whale would not be possible for at least 75 years. It is not even sure whether eventual recovery would take place. This is because of a lack of knowledge from the genetic restrictions imposed on the species by its low numbers. As of December 31, 1998, Eubalaena glacialis was listed as endangered under the Endangered Species Act and depleted under the Marine Mammal Protection Act for the North Atlantic, North Pacific, and the Bering Sea.

Today it has become a management challenge to regulate the ship industry and their contact with right whales. From the mariner's perspective, collisions are rare and unintentional, and it is impossible to see the whales beyond a few hundred yards. To meet this challenge, efforts have been focused on the following approaches: (1) modifying operating procedures for government vessels that frequently transit key right whale habitats, (2) establishing early warning systems to advise vessel operators of the location of whales on a real-time basis and on the need for special caution, (3) preparing educational materials for mariners on the need and ways to avoid hitting right whales with ships, (4) developing mandatory ship reporting systems in key right whale habitats, and (5) conducting research to better understand and mitigate collision risks.

References: (All information came from the Annual Report. Marine Mammal Commission's Annual Report to Congress in 1998. Publication was January 31, 1999. Pgs. 3-24.

The northern elephant seal, Mirounga angustirostris had an original range from San Francisco to Magdalena, Bay on the Baja Peninsula in Mexico. The southern elephant seals live around Antarctica. In 1818, man began hunting the northern elephant seal for the oil found in its blubber. The oil was used for many of the same uses as whale oil including the manufacture of edible fats. A large bull would yield up to 350 L of oil. By 1860, due to hunting pressure the northern elephant seal was virtually extinct. In 1892, there was only one surviving group of no more than 100 northern elephant seals on Guadalupe Island off of the Baja Peninsula.

The northern elephant seal has made a remarkable recovery. The 1911 Fur Seal Protection Act put a stop to the hunting and allowed angustirostris to make a recovery. Incidental take from fishing is not believed to have had a major effect on northern elephant seal populations (Sydeman, 1999). The only predators of the adult angustirostris besides man are great white sharks and killer whales.

Despite its remarkable recovery, northern elephant seal faces dangers to its population. All of the existing northern elephant seals came from the Guadalupe colony of less than 100 animals. Today they all share exactly the same blood proteins. This lack of genetic diversity could prove damaging if the species confronts a new disease or rapidly changing environmental conditions. Northern elephant seals have a space conflict with man around some of their breeding rookeries. In central California near the Piedras Blancas breeding colony in 1998, 4 subadult males were killed by cars after being driven from the colony by larger adult males (Hatfield, 1999). Field fencing with barbed wire has proved effective in keeping the seals out of dangerous areas. However, there are still many areas where the fencing is not yet present.

The northern elephant seal has expanded its pupping range beyond its original range (Hodder, 1998). Shell Island, Oregon is a new breeding location despite the tendency for winter storms that often decimate the newborn pups. This expansion is due to the pressures from the continued population growth of angustirostris. Seals have also been seen coming ashore on the coast of Washington.

In 1741, the Russians discovered a colony of northern sea otters on the Commander Islands, lying to the west of the Aleutian Islands. Sea otters, Enhydra lutris have one of the most valuable furs of any mammal. The Russians enslaved Native Aleutians and forced them to hunt the sea otter across the Aleutian Islands and off the coast of Alaska. In the process, the hunters caught Stellar Sea Cows for food and drove them to extinction within 15 years. Sea otter furs could be purchased on the London Market in 1880 for $165 and in 1903 for $1125 when the otters became scarce. As otters became scarce in the North, the Russians moved southward along the coast of western North America to California. Here they encountered the California sea otter, Enhydra lutris nereis with a population of 16,000 – 20,000 otters (Riedman, 1990). The Americans and English joined in on the hunting and by 1911, there were only 1000-2000 Enhydra lutris worldwide. By 1920, the California sea otter was thought to be extinct.

One secret colony of California sea otters survived off Monterey, near Point Sur. The Point Sur colony had as few as 32 otters living in the seclusion provided by the rugged coast (Riedman, 1990). Locals and scientists knew about the otters but kept their existence secret. The 1911 Fur Seal Act gave protection to otters as well as seals and sparked their recovery. In 1911, there were only 12 remaining northern sea otter colonies and the one remaining California sea otter colony. The original range of the California sea otter was from the Washington coast to the Baja Peninsula. Now their range occupies only 220 miles of coastline from just south of San Francisco to Santa Maria.

One of the major obstacles to the recovery of the California sea otter has been a conflict of resources with the shellfishing industries. Otters, being keystone predators, significantly reduce populations of abalones, clams, and sea urchins (Mason, 1986). The shellfishing industries for ablones and clams began at the start of the century when sea otters were scarce. As sea otters have made a gradual come back over the last century they have competed with the shellfishing industries. Some of the shellfishing industries have declined drastically due in part to the sea otters, but also due to overfishing and poor management. The shellfishers have blamed the comeback of the sea otter on declines in their catches. One management approach endorsed by shellfishers involves otter-free zones where otters are relocated when found in a shellfishing area (Gerber, 1999). This experimental management method has not been successful. Relocating otters is very expensive and the relocated otters can breach the carrying capacity of their new home. Recent advances in mariculture look promising for the abalone industry. Many restaurants are using abalones grown in mariculture. This may help relieve the resource conflict with sea otters.

Oil spills remain a large threat to the California sea otter population. The Valdez oil spill killed more than 2000 northern sea otters. Such a spill would wipe out the entire California sea otter population of about 2000. Oil companies have restrictions on exploration within the California sea otter’s range. Some companies have plans for cleaning oiled otters, which is an exhaustive and highly unsuccessful process. The oiled otters must be tranquilized and washed repeatedly with dishwashing soap to remove all traces of the oil.

In 1987, the USFWS started a translocation program for the California sea otter (Riedman, 1990). By 1990, 137 otters were transplanted to San Nicolas Island lying to the south of the otter’s present range. Of the 137 transplanted only 14 remained around the island. Twenty-seven adults swam all the way back home, a distance of 72 kms, even though otters are not known to be a migrating species. Most of the lost otters were not accounted for. Translocations typically take many years to be successful for any species.

The California sea otter made a slow but steady increase in population from 1930-1970 to reach 1200-1300 otters (Mason, 1986). In the 1980’s there was a slight decline in the population. The use of gillnets and trammel-fishing nets were identified in the deaths of many otters during this time. In January 1985, an emergency closure of fishing was ordered in less than 90 feet of water (sea otter’s foraging range) along the California coast. The population began to increase up until 1995. The latest numbers show a decline of the population back to 2100 otters in the spring of 1999 and less than 2000 otters in the fall of 1999. The causes of the latest decline have not been identified.

References:

Gerber, LR, Wooster, WS, DeMaster, DP, and VanBlaricom, GR. 1999. Marine mammals: new objectives in U.S. fishery management. Reviews in Fisheries Science. 7 (1): 23-38.

Hatfield, BB and Rathburn, GB. 1999. Interactions between northern elephant seals and vehicles near Point Piedras Blancas, California. Marine Mammal Science. 15 (2): 598-600.

Hodder, J, Brown, RF and Cziesla, C. 1999. The northern elephant seal in Oregon: a pupping range extension and onshore occurrence. Marine Mammal Science. 14 (4): 873-81.

Mason, C.F. and Macdonald, S.M. 1986. Otters: ecology and conservation. Cambridge, U.K.; Cambridge University Press. p 190-200.

Riedman, M. 1990. Sea Otters. Monterey, Ca: Monterey Bay Aquarium; p 1- 40.

Sydeman, WJ and Allen, SG. 1999. Pinniped population dynamics in central california: correlations with sea surface temperature and upwelling indices. Marine Mammal Science.15 (2): 446- 61.

Gray whales- (Eschrichtius robustus)

They are a slate gray mysticete ranging from 13-14 m in length, females slightly longer than males (Novak, 1983). Like various other cetaceans, humans have killed gray whales for their oil, meat, hides, and baleen. In ancient times, they were hunted by natives of northwestern North America, eastern Siberia, Europe and Japan (Novak, 1983). Gray whales are presently found on the eastern and western side of the Pacific (Leatherwood, 1983). The western stock was initially small in numbers. Thus, once the Japanese began to not only hunt but industrialize, the numbers hovered around extinction on the western side of the Pacific (Novak, 1983). The European population became extinct around 500 A.D.; whereas, the Atlantic population disappeared around the 1700’s (Novak, 1983).

Whaling became the largest stress applied to the continuation of gray whale populations when shore whalings were established in 1846 (Novak, 1983). In a twenty-eight year period following the establishment of whaling stations, 10,800 whales were subsequently killed. Thus, around 1900 regular shore whaling stopped because the population seemed extinct. Norwegians, Japanese and Russians shortly thereafter utilized factory ships to hunt the gray whale. From 1921-1947, approximately 1,100 whales were killed (Novak, 1983). In this time (1930), the League of Nations placed a ban on gray whaling but the nations using factory ships were not members, thus they need not oblige (Annual Report, 1998). Finally, in 1946 the International Whaling Commission protected the gray whales due to being seen as "commercially extinct" (Day, 1987). Even though the IWC placed a ban on commercial gray whaling, over 200 non-commercially kills were performed annually by Eskimos and Siberian aborigines (Caulfield, 1997). Eskimos kill grays for cultural reasons, whereas Siberians mask their kills as also being "cultural". "Cultural" in Siberian sense of the word is not used for indigenous means but for fodder to supply their growing mink farms (Day, 1987).

Currently, the eastern Pacific stock exhibits the greatest numbers. Their migration is the longest of any mammal, 7,000 miles from the Arctic waters of Alaska/Siberia (Bering and Chukchi) to the tropical waters of Baja (Day, 1987). The grays migrate in shallow nearshore waters, thus a significant whale watching industry has been established. Most gray whales begin their migration between October and January and arrive at their Baja calving grounds in January or February (Leatherwood, 1983). Then from late February to June, the whales and their new calves begin their northward migration to their summering grounds off the Arctic where upwelling brings the nutrients needed to support the calves (Novak, 1983).

Two of the foremost calving grounds occur in Ojo de Liebre and Guerrero Negro, two lagoons in Baja. Many studies were performed in these areas to identify key factors which cause gray whale mortality in the lagoons (Sanchez Pacheo, 1998). Most calves died to separation from mothers by males, strong currents or vessels. Once separated, the calves become disoriented, exhausted and thus die (Sanchez Pacheo, 1998). Calves were also observed being severely struck by adult whales involved in mating groups; thus these blows could have led to death. Several species of large sharks, abundant in the calving grounds, may also account for gray whale calf mortality (Leatherwood, 1983). During their migration northward, killer whales may cause significant young gray whale mortality. Gray whales have exhibited killer whale bite scars, and killer whales have been seen feeding on gray whale tongues while leaving the carcass for scavenging (Leatherwood, 1983). Lastly, humans continually cause gray whale mortality even with IWC’s laws. Industrialization and boat traffic not only adversely change their environment, but also directly disorient and eventually kill the grays. A salt processing factory seeks establishment near their calving grounds; thus it would not only cause detrimental effects to the environment but also may kill more gray whales and is subsequently unwelcomed(Annual Report, 1998).

In 1976, the first whale sanctuary was established in the Baja lagoons. By 1978, the IWC reclassified the Eastern Pacific gray whale stock from protected to sustained-management (Day, 1987). The other stock remained commercially extinct. Then in 1994, the eastern stock was taken off both the Endangered Species, as well as, the Threatened Species List (Annual Report, 1998). Presently, 23,000 Eastern Pacific gray whales exist which is nearly the same number as before the exploitation began. Unfortunately, the Western Pacific gray whale stock is still one of the world’s most endangered species (Annual Report, 1998). Thus, human intervention not only caused gray whale mortality, but in the end was able to bring most of the population back to acceptable levels. Currently, humans cause less moralities than in previous years and nature is now keeping the balance in the oceans.

References:

Annual Report to Congress (1998). Marine Mammal Commission. Pgs. 27-32.

Caulfield, R.A. 1997. Greenlanders, whales, and whaling: Sustainability and self-determination in the Arctic. UP of England; Hanover. 203 pp.

Day, D. 1987. The whale war. Sierra; San Francisco. 168 pp.

Leatherwood, Stephen and Randall R. Reeves. 1983. The Sierra Club Handbook of Whales and Dolphins. Sierra Club Books; San Francisco. Pgs. 77-82.

Novak, Ronald M., and John Paradiso. 1983. Walker's Marine Mammals of the World. 4^th Edition. Johns Hopkins University Press; Baltimore. Pgs. 911-913.

Sanchez Pacheo, J.A. Jan. 1998. Gray whale mortality at Ojo de Liebre and Guerrero Negro lagoons, Baja California Sur, Mexico: 1984-1995. Mar. Mamm. Sci. 14 (1): 149-55.