North Pacific Right Whale: Wikis

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North Pacific Right Whale[1]
Size comparison against an average human
Conservation status
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Cetacea
Family: Balaenidae
Genus: Eubalaena
Species: E. japonica
(Lacépède, 1818)
Binomial name
Eubalaena japonica
Range map
Synonyms
  • sieboldii (Gray, 1864)

The North Pacific Right Whale (Eubalaena japonica) is a very large, robust baleen whale species that was common in the North Pacific until 1840, but now extremely rare due to 19th and 20th century whaling. There are apparently two populations of the species in the North Pacific. A population that occurs in the southeastern Bering Sea and eastern North Pacific may be 50 animals or less. A very poorly known population in the Sea of Okhotsk between the Kuril Islands and Sakhalin Island in Russia may number 300 or more animals, but there is almost no data on this population. Although the whales have been protected from whaling since 1935, illegal Soviet whaling in the 1950s and 60s depleted their numbers further. The International Union for the Conservation of Nature has expressed concern that its numbers are now too low for recovery, and that extinction may be inevitable. According to the Center for Biological Diversity, the North Pacific Right Whale is the most endangered whale on Earth.[3]

Contents

Taxonomy

The North Pacific Right Whale is a member of the family Balaenidae, and all species of this family are often lumped together in popular accounts as "right whales". This family consists of two genera: Balaena—with one species, the Bowhead Whale of the arctic (B. mysticetus), and Eubalaena—the "right whales", also often called "black right whales". The much smaller Pygmy Right Whale (Caperea marginata) of the Southern Hemisphere is considered to be in different family, Neobalaenidae.

Until recently, all right whales of the genus Eubalaena were considered a single species--E. glacialis. In 2000, genetic studies of right whales from the different ocean basins led scientists to conclude that the populations in the North Atlantic, North Pacific and Southern Hemisphere constitute three distinct species which they named: the North Atlantic Right Whale (Eubalaena glacialis), the North Pacific Right Whale (Eubalaena japonica) and the Southern Right Whale (Eubalaena australis).[4] Further genetic analysis in 2005 using mitochondrial DNA and nuclear DNA has supported the conclusion that the three populations should be treated as separate species,[5] and the separation has been adopted for management purposes by the U.S. National Marine Fisheries Service and the International Whaling Commission.[6]

Description

North Pacific Right Whale by John Durban, NOAA

The North Pacific Right Whale is a very large, robust baleen whale. It very closely resembles the other right whale species—the North Atlantic Right Whale (E. glacialis) and the Southern Right Whale (E. australis). Indeed, without knowing which ocean an individual came from, the physical similarities are so extensive that individuals can only be identified to species by genetic analysis.

The North Pacific Right Whale is easily distinguished in the wild from other whale species in the North Pacific. Right whales are very large and can reach 18.3 m (60 ft) in length, substantially larger than the Gray or Humpback Whales. Right whales are also very stout, particularly when compared to the other large baleen whales such as the Blue and Fin Whales. For 10 North Pacific Right Whales taken in the 1960s, their girth in front of the flippers was 0.73 of the total length of the whale.[7]

North Pacific Right Whale, Half Moon Bay, California, March 20, 1982 by Jim Scarff

Right whales are the only baleen whale species in the North Pacific that lack a dorsal fin altogether. Right whales are also unique in that all individuals have callosities—roughened patches of epidermis covered with aggregations of hundreds of small cyamids that cluster on the callosities. As in other species of right whales, the callosities appear on its head immediately behind the blowholes, along the rostrum to the tip which often has a large callosity, referred to by whalers as the "bonnet".[7]

The species most similar to the North Pacific Right Whale in the North Pacific/Bering Sea area is the closely related Bowhead Whale. Both species have huge heads that constitute up to one-third of the body length, highly arched mouths, very long, fine baleen, no dorsal fin, and great breadth. However, the seasonal ranges of the two species do not overlap. The Bowhead Whale is found at the edge of the pack ice in more Arctic waters in the Chuckchi Sea and Beaufort Sea, and occurs in the Bering Sea only during winter. The Bowhead Whale is not found in the North Pacific. Bowhead whales completely lack callosities, the easiest way to distinguish the two species in photographs.

Although more than 15,000 right whales were killed by whalers in the North Pacific,[8], there are remarkably few detailed descriptions of these whales. Most of our information about the anatomy and morphology of the North Pacific Right Whale comes from 13 whales killed by Japanese whalers in the 1960s[9] and 10 whales killed by Russian whalers in the 1950s.[10] Basic information about right whale lengths and sex are also available from coastal whaling operations in the early part of the 20th century.[11]

Relative to the other right whale species, the North Pacific Right Whale may be slightly larger. The largest North Pacific Right Whale ever recorded was an 18.3 m (60 ft) female.[10] Like other baleen whales, female North Pacific Right Whales are larger than males. Brindle-colored individuals are less common than they are among the Southern Right Whale.

Population

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Historic Population

Before being decimated by pelagic whalers in the mid-19th century, right whales were common in the North Pacific. The number of right whales killed in Japanese shore-based net whaling or by Native American whalers in the Aleutians was almost certainly so small that it did not reduce the overall population size. Accordingly, one can consider 1835 as a good year to use as a baseline for the historic population. In the single decade of 1840-49, between 21,000-30,000 right whales may have been killed in the North Pacific, Sea of Okhotsk and Bering Sea.[8] This suggests that right whales may have been as abundant as the Gray Whale in the North Pacific.

Current Population

Southeastern Bering Sea & Gulf of Alaska

Several writers have attempted to estimate the total population of right whales in the southeastern Bering Sea and Gulf of Alaska, often referred to as the eastern North Pacific population. A comprehensive review of sighting data and population estimates in 2001 concluded that "none of the published estimates of abundance relating to North Pacific right whales can be regarded as reliable...[most] estimates appear to be little more than conjecture...[and] no quantitative data exist to confirm any of these estimates."[12]

North Pacific Right Whale in the Bering Sea, summer 2004 by Bob Pitman, NOAA

All that can be said with any confidence is that as of 2004, there were at least 23 right whales in the southeast Bering Sea, since that number of whales were seen in two separate sightings in August.[6] From biopsy samples, it was determined that 10 were males and 7 females, and at least two of the whales were calves.[13] Prior to that sighting, extensive aerial and acoustic surveys in the southeastern Bering Sea and the Gulf of Alaska had not revealed more than six right whales in any year.[14] In 1998 and 2004 an individual right whale was seen in the Gulf of Alaska near Kodiak Island and right whale calls were recorded from this area in 2000.[15]!

In a December 2006 status review of right whales, the U.S. National Marine Fisheries Service (NMFS) stated: "Recent sightings suggest that the abundance in the eastern North Pacific is indeed very small, perhaps in the tens of animals." [6] The U.S. Marine Mammal Commission in its 2006 Annual Report stated that "the eastern population may now number no more than 50 individuals." [16] A 2008 report by researchers "the extreme rarity of sightings in recent decades suggests that the population numbers in the tens." [17]

The proposed oil and gas lease of North Aleutian Basin in the SE Bering Sea caused the Minerals Management Service (MMS) of the Department of the Interior to fund at an annual cost of about $1 million a cooperative series of annual surveys with the National Marine Fisheries Service and the North Pacific Research Board (NPRB), with a focus on located right whales and gathering further information about them. In 2007, from July 31 to August 28 an international team of scientists conducted shipboard surveys of an area almost the size of New York in search of Pacific right whales. "We did not see a single whale the entire time," said Phil Clapham, team leader and chief scientist with the National Oceanic and Atmospheric Administration's Alaska Fisheries Science Center in Seattle. "The bottom line, they were not in the places they had traditionally been in the last six or seven years" The research is required under the federal Endangered Species Act because the area where the whales like to spend summers overlaps an area the federal government in 2007 approved for oil and gas development. Lease sales could begin by 2011. The whales weren't found this summer because it is a "cold pool year" in the Bering Sea, Clapham said. That means the water is colder than normal. The colder water likely affected the distribution of plankton, which is what the large whales feed on, he said.[18]

In the summer 2008, follow-up aerial and shipboard surveys were conducted by NMFS (funded again by the MMS and the NPRB) 22 July – 31 August and 2 August – 12 September to investigate distribution, movements and ecology of right whales in the BS both in general as well as with respect to the planned oil lease. During these respective survey periods a total of 10 sightings (of 12 individuals) and 22 sightings (of 34 individuals) were recorded, respectively, including duplicate counts between platforms. All occurred within the North Pacific Right Whale Critical Habitat in the Bering Sea.

An Argos PTT satellite transmitter was deployed in one and the whale was monitored for 58 days, a period in which it remained in a relatively small area within the middle shelf of the Eastern Bering Sea, just to the north of the North Aleutian Basin. The number of whales photo-identified from ship and aerial surveys were 7-9 and 6, respectively, resulting in the identification of 9-11 ndividuals in total. The re-sighting rate of individuals was high for a whale population—four whales were seen by both survey platforms, indicating that a small number of individuals occurred in the survey area. Five whales seen in 2008 were also previously photographed in the Bering Sea in 1996-2002, and in 2004. One of these individuals was a whale tagged in 2004.[19]

Sea of Okhotsk

Pelagic whalers in the 19th century hunted large numbers of right whales along the coasts of Kamchatka and in the Sea of Okhotsk. The latter area is a large sea, ice covered most of the year, entirely in Russian waters. Due to Russia restrictions on access, little was known about whales in this sea. However, in the late 1980s and early 1990s, Japanese research vessels in the Sea of Okhotsk reported 28 sightings of right whales in the Sea of Okhotsk. From this sample, the Japanese scientists estimated a population of 900 right whales in the Sea of Okhotsk, albeit with low confidence intervals (90% CI = 400-2,100).[20] After a gap of 14 years, Japanese researchers were able to resurvey this area in 2005 and apparently saw similar numbers of right whales in the same area. Other scientists have disputed the methodology used to extrapolate a total population size, and contend that the population may be less than half of that.[12] However, it appears that there is a small population of right whales that summers in the Sea of Okhotsk. Where these whales go in winter is unknown.

Ecology and Behavior

Food

Like right whales in other oceans, the North Pacific Right Whales feed primarily on copepods, mainly the species Calanus marshallae.[21] They also have been reported off Japan and in the Gulf of Alaska feeding on copepods of the genus Neocalanus with a small quantity of euphausiid larvae Euphausia pacifica.[6]

Like other right whale species, the North Pacific Right Whale feeds by skimming water continuously while swimming, in contrast to balaenopterid whales such as the Blue and Humpback Whales which engulf prey in rapid lunges. Right whales do not have pleated throats. Instead they have very large heads and mouths that allows them to swim with their mouths open, the water with the copepods flowing in, then flowing sideways through the right whale's very long, very fine baleen trapping the copepods, and then out over their large lower lips.

Given the tiny size of copepods, it takes millions of them to provide the energy a right whale needs. Thus, right whales must find copepods at very high concentrations. Researchers studying the North Atlantic Right Whale concluded that right whales needed concentrations of >3,000 copepods per m3 to feed efficiently. NMFS researchers have recently mapped the southeast Bering Sea and the Gulf of Alaska for areas of productivity that would support such concentrations of copepods and analyzed the role of Bathymetry and various gyres in the concentration of copepods to densities that could support right whale's feeding.[21]

Behavior

A breaching right whale, Half Moon Bay, California, March 20, 1982, photo by Jim Scarff

There have been very few, short visual observations of right whale behavior in the North Pacific. The massive amount of whaling on this species in the mid-19th century occurred before there was much scientific interest in whale behavior, and included no observations by trained scientists. By the time scientific interest in this species developed, there were very few right whales left and no place in the eastern North Pacific or Bering Sea where one can go and reliably find them. So far, scientists have had only minimal success attaching long-term satellite tags to North Pacific Right Whales.[13] The few observations of right whales have generated probably less than 50 hours of observations during opportunistic encounters over the last 50 years. What little is known about North Pacific Right Whale behavior suggests that it is similar to the behavior of right whales in other oceans, although it may differ significantly in its choice of wintering grounds.

Spectogram of a right whale "upcall" recorded in the SE Bering Sea, Sue Moore, NMFS National Marine Mammal Laboratory (help in interpreting spectograms)

There have been some noteworthy non-visual observations of these whales. NMFS biologists have deployed various passive acoustic listening devices in the Bering Sea and Gulf of Alaska in attempts to record calls of right whales. The scientists were able to record at least 3,600 North Pacific Right whale calls between 2000-2006. Nearly all of these calls came from the shallow shelf waters (~70m depth) of the southeastern Bering Sea in what is now designated Critical Habitat for this species. 80% were frequency-modulated "up-calls" with on average from 90–150 Hz and 0.7 second duration. "Down-up" calls constituted about 5% of the calls, and swept down for 10-20 Mz before becoming a typical "up-call". Other call types, e.g. downsweeps and constant-tonal "moans" constituted less than 10% of total calls. The calls were clumped temporally—apparently involving some level of social interaction, as has been found in the calls of right whales in other oceans. The whales tended to call more at night than during the day.

Recordings are available online from North Atlantic Right Whales of "up-calls" as well as "moans", "screams" and "gunshot" calls.

The very small number of North Pacific Right Whale calls detected during the NMFS research—hundreds per year contrast with the vastly greater number (hundreds of thousands) of bowhead whale calls during migration in the western Arctic and blue whale calls off California—further reinforces the conclusion that the population size of North Pacific Right Whales in the Bering Sea is very small.[22]

Distribution

Historic

Before 1840, the distribution of the North Pacific Right Whale was extensive and had probably remained the same for at least hundreds of years. The right whales were distributed from the Sea of Okhotsk in the west east all the way to the western coast of Canada. The seasonal movements and the densest concentrations of whales, then as now, are unknown.

To determine where the right whales were, an imaginative cooperation developed between the whalers and one of the country's first oceanographers. In the 1840s the principle mariners who ventured away from the main trade routes were whaling ships. The description of currents, winds, and tides in these remote regions was of great interest to the U.S. Navy. Accordingly, Naval Captain Matthew Fontaine Maury made a deal with whalers—if they would provide him with their logbooks from which he could extract wind and current information, he would in return prepare for them maps showing where whales were most concentrated. Between 1840-1843, Maury and his staff extracted data from over 2,000 whaling logbooks and produced not only the famous Wind and Current Charts used by mariners for over a century, but also a series of Whale Charts. The most detailed of these Whale Charts showed by month and 5° of latitude and longitude (a) the number of days on which whaling ships were in that sector, (b) the number of days on which they saw right whales, and (c) the number of days on which the saw sperm whales". In the North Pacific, these charts contain records of over 8,000 days on which the whalers encountered right whales as well as a record of the searching effort by month and sector. The resulting maps thus contain a crude measure of the relative abundance of right whales by geographic sector and month, controlled for the very non-random searching effort of the whalers.

The whalers in the North Pacific hunted right whales mainly in the summer, and that is reflected in the Maury Whale Charts. There were almost no sightings in winter and very few south of 20°N. The densest concentrations of whales occurred along both coasts of Kamchatka and in the Gulf of Alaska.[23]

In 1935, Charles Townsend from the New York Zoological Society (now the Wildlife Conservation Society) reviewed 2,000 logbooks of American whaleships and mapped on several large Charts the locations of each species of whale taken as recorded in the logbooks. His Chart C shows the location of catches of right whales around the world. In the North Pacific, Sea of Okhotsk and Bering Sea, Chart C shows the location by month of most of the 2,118 right whales taken in the North Pacific between 1839-1909 using data copied from logbooks of 249 cruises by American whaleships in the North Pacific. His Charts do not attempt to adjust for the nonrandom distribution of whalers, so they are biased to an unknown extent to reflect the location of the whalers who tended to favor more coastal, more protected, and closer waters. Townsend's Chart C also shows three main concentrations of right whales—one in the Gulf of Alaska; one along Kamchatka and the Sea of Ohotsk; and another in the Sea of Japan.[23][24]

Of particular interest are the questions of how many "stocks" of right whales exist in the North Pacific. Was there just a single population across the North Pacific? Was there an eastern population that summered in the Gulf of Alaska and a second population in the western North Pacific. Was the population in the Sea of Ohotsk a third population distinct from the whales found in the Pacific east of Kamchatka?

Recently, researchers made a more rigorous analysis of this early whaling data, along with the more recent but much sparser recent sighting data. They conclude that there are probably at least two stocks of right whales in the western and eastern North Pacific, but that it was still unclear whether the population in the Sea of Okhotsk was a separate stock.[21][25]

The North Pacific Right Whale's distribution is more temperate than that of the more polar Bowhead whale, and there are no records of the two species being in the same area at the same time. The North Pacific Right Whale's summer distribution extends north into the southeastern part of the Bering Sea. In summer, the Bowhead has migrated north through the Bering Straits and is in the Chukchi and Beaufort Seas. In winter, the ice-loving Bowhead moves south back into the Bering Sea, but the right whales have migrated south of the Aleutian Islands into the North Pacific.

Modern

Bering Sea & eastern North Pacific

Map of sightings of right whales in the Bering Sea and Gulf of Alaska 1973-2007 and designated critical habitat

Despite massive amounts of searching effort by aircraft and ship-based observers,[26] as well as acoustic listening devices, the recent records of right whales in the eastern North Pacific have been limited to a few small areas. Most of the sightings have been in the southeastern Bering Sea, with a few in the Gulf of Alaska, and even fewer in California in winter. In 2000, 71 right whale calls were found from a deep-water passive acoustic site at 53° N 157 W. These are in addition to 10 previously found from near Kodiak Island in the Gulf of Alaska at 57°N 152°W[27] In 2004, two groups seen in Bering Sea one of two whales on August 10, the other in September of 17 whales, including two calves and one in Gulf of Alaska.[13] In 2005, 12 right whales were seen in October just north of Unimak Pass, Bering Sea.[6]

Review of >3,600 North Pacific Right Whale calls detected by passive acoustic listening devices between 2000-2006 strongly suggests that the whales migrate into the southeast Bering Sea (presumably from the North Pacific) in late spring and remain there until late fall. The earliest recorded calls were detected in late May and the latest in December. The peak of calling occurred during July through October. Although most of these calls were detected by acoustic devices located on the shallow southeast Bering Sea shelf within the designated Critical Habitat area, in October through December 2005, several calls were detected outside the Critical Habitat area on the northwestern middle-shelf and from the deeper shelf site, suggesting that these sites may be important at different seasons and be important during migration.[28]

Western North Pacific and Sea of Okhotsk

There are very few records of right whales in the western North Pacific.

Map of Sea of Okhotsk

There appears to be a remnant population in the Sea of Okhotsk, along with remnant populations of the eastern stock of Gray and Bowhead Whales, however the distribution of these three species is quite different. The Bowhead Whales are found in summer in the northwestern corner of the Sea of Okhotsk. The Gray Whales are found close to Sakhalin Island, an area near where there is massive new energy developments. In contrast, the North Pacific Right Whales are found in the southern portion of the Sea of Okhotsk nearer the Kuril Islands and northeast of Sakhalin Island. Unfortunately, this area is extremely remote and access is very difficult and expensive.

Migration and winter range

The wintering grounds for right whales in the North Pacific remain a great mystery still. The other right whale species tend to have large portions of the population wintering extremely close to shore. However, no such coastal wintering ground has been found for right whales in the North Pacific.[23][25]

Some right whales migrate south along both coasts of Japan particularly the pacific side. Occurrences in the Japan Sea, East and South China Seas, and Yellow Sea are very rare in modern.[29]

Recently, several sightings of right whales have been made. For example, at least two individuals were sighted off the coast of Kii Peninsula, one of the major historical whaling grounds in spring-summer 2006, giving some opportunities for whale-watchers to observe.[30] An adult animal was trapped in a fishing net and then escaped off Taiji Town in January 2009.[31][32] Short footage is available(in Japanese).[33] There has been speculations that the whales may have wintered in the Bonin Islands, but there are few sightings from this area in recent decades.[34] A sighting of two animals occurred just off Mikura island in March, 2008.[35]

Until recently, most researchers thought that right whales in the eastern North Pacific migrated to wintering grounds off the west coast of North America, particularly along the coasts of Washington, Oregon and California. There have been a few sightings in winter in all these areas, particularly in California to support this hypothesis. However, a more detailed study of these sightings argues that the single whales seen off California, Baja, and Oregon were merely "stragglers" from the main population. Notwithstanding large whale-watching operations that operate 7 days a week year around in several parts of this range, there have only been 17 sightings of right whales between Baja and Washington state.[36] The absence of any calves in the stranding data from California further suggests that coastal western North America were never in historic times important calving or wintering grounds for right whales in the North Pacific.[37]

Conservation

Challenge #1 - Finding Right Whales

The major threshold problem for conserving this species is locating any right whales. The two other species of right whales have known areas where they can be reliably found either on their winter grounds (Florida, South Africa, Argentina, Brazil, Australia) or on their summer feeding grounds in the western North Atlantic.[38] There are no locations in the North Pacific, Bering Sea or Sea of Japan where right whales can reliably be found. Perhaps they can be reliably found in the Sea of Okhotsk, but that area is so remote, getting researchers there becomes the number one problem.

The species is so rare that the National Marine Fisheries Service has had only intermittent success in locating North Pacific Right Whales in the southeast Bering Sea and Gulf of Alaska notwithstanding much searching effort. Small numbers of right whales were located in the Bering Sea in 1966 [39] and 1997-2004.[26][40]. However, a month of dedicated research cruises in that area in August 2007 failed to sight a single right whale. This tiny population was someplace else.[41]

In winter, the whales' location is particularly mysterious. There have been a few records from California and even Baja, particularly in the 1990s. However, despite enormous amounts of searching effort along these coasts by observers in whale-watching boats and other boats, these records have been rare and of short duration.North Pacific Right Whales - The Forgotten Species

In the Sea of Okhotsk, the right whales appear to be found far from shore in the southern part of the sea. The Sea is all Russian territorial waters, so Russian cooperation is required for any surveys. The remoteness of the location and the enormous demand for ships and aircraft associated with oil and gas exploration near Sakhalin Island, would make any ship or aerial surveys difficult and expensive.

One new technology that holds promise for finding right whales is passive acoustic listening. Passive listening devices are placed on the sea floor and record for hundreds of hours. The technology is able to detect right whales that are submerged. It works in low visibility conditions and can record for long periods of time.[42][43]

Another technology that could provide enormous amounts of new information about this species are satellite-monitored radio tags. These are non-lethal tags applied to a right whale, usually by means of a crossbow, that can track the whales' location, movements, dives and other information nd beam it back to researchers with a satellite. The technique has been used successfully in the North Atlantic. The tags are expensive and there are not many of them. The challenge is to get the tag and the right whale together at the same time and place.

Acoustic detection and satellite tags can work together. In August 2004, researchers from the National Marine Fisheries Service in the southeastern Bering Sea detected right whale vocalizations from passive acoustic listening devices. The researchers then deployed directional frequency and ranging sonobuoys to determine the direction and location of the calling whales. With this information the researchers were able to find two right whales, photograph them, taken genetic samples, and attach satellite tags. Only one of these tags transmitted locational data, and that failed after 40 days during which period the whale moved throughout a large part of the southeast Bering Sea shelf, including areas of the outer shelf where right whales have not been seen in decades. Unfortunately, just as the whale was expected to start its southern migration, the tag failed for unknown reasons.[13]

Threats to their survival

So little is known about North Pacific Right Whales that any description of the threats they face necessarily involves some speculation. Much more is known about the threats faced by North Atlantic Right Whales, so a review of those threats is a good place to start.

Minimum sustainable population size

When populations of wild animals get very small, the population becomes much more vulnerable to certain risks than larger populations. One of these risks is inbreeding depression.[6]

A second risk of very small populations is their vulnerability to adverse events. In its 2006 Status Review, NMFS stated the North Pacific Right Whale's low reproductive rates, delayed sexual maturity, and reliance on high juvenile survivorship combined with its specialized feeding requirements of dense schools of copepods "make it extremely vulnerable to environmental variation and demographic stochasticity at such low numbers".[6] For example, a localized absence of food for one or more years may be all that is needed to reduce the remaining population below a minimum size. As the NMFS Status Review notes: "Zooplankton abundance and density in the Bering Sea has been shown to be highly variable, affected by climate, weather, and ocean processes and in particular ice extent."[6]

A third risk is the increased difficulty of finding mates. North Pacific Right Whales must find mates, and with so few whales in such a large area, this is increasingly difficult. Past sightings of right whales suggest that the animals generally travel alone or in very small groups. In other oceans, breeding female whales have been seen attracting mates by calling underwater. The success of such calls depends upon a male whale being within hearing range. As the background noise of the ocean has increased due to ship traffic, the range over which such mating calls can be heard has decreased.

Oil spills, exploration & extraction

Current commercial shipping in the right whale's range creates the threat of oil spills. In 2005 the wreck of the M/V Selendang Ayu near Unalaska caused the release of approximately 321,000 gallons of fuel oil and 15,000 gallons of diesel into the Bering Sea.

The search for new oil and gas fields and their subsequent development and operation involves several threats to right whale survival. In its 2006 Status Review, NMFS notes that the development of the Russian oil fields off the Sakhalin Islands in the Sea of Okhotsk "is occurring within the habitat" of the western population of North Pacific Right Whales.[6]

On April 8, 2008, a NMFS review found that there had been no recent Outer Continental Shelf oil and gas activities in or adjacent to the areas designated as critical habitat for the North Pacific right whale.[44] However, on the same day the U.S. Minerals Management Service (MMS) published a notice of a proposed Oil and Gas Lease Sale 214 for 5,600,000 acres (22,700 km2) in the North Aleutian Basin. MMS announced the beginning of preparation of an environmental impact statement for this lease. If the lease goes forward, the sale of the rights would occur in 2011 and exploratory drilling could begin in 2012. [3] More than half the proposed lease sale area is within the designated critical habitat of the North Pacific right whale (see map). The Center for Biological Diversity is continuing its lawsuit to shut down this lease sale.[45]

The exploration phase is characterized by numerous ships engaged in seismic testing to map undersea geological formations. This seismic testing involves very loud blasts of noise which echo off the undersea rock formations. These explosions have been considered to be such a threat to the closely related bowhead whale that they have been banned in the Beaufort Sea during the time of year that the bowheads are present. In its 2006 Status Review, NMFS reviews the scientific studies on the effects of noise pollution on marine mammals and concludes: "In general, the impact of noise from shipping or industrial activities on the communication, behavior and distribution of right whales remains unknown."[6]

Adverse changes to the whales' environment

The habitat of the North Pacific Right Whale is changing in ways that threaten the survival of the species. Two environmental effects of particular concern are global warming and increased pollution.

Right whales are specialized feeders that depend on extremely dense concentrations of copepods to meet their energy requirements. If the copepods cannot be found in these high concentrations, right whales are poorly adapted to feed on alternate prey. In turn, the high densities of copepods are the result of high phytoplankton productivity and currents which aggregate the copepods into concentrations high enough for the right whales to feed efficiently. The satellite tag studies of right whales have shown them traveling considerable distances to find these localized concentrations of copepods.

Global warming can affect both the population levels of copepods generally and the oceanographic conditions which cause the high concentrations right whales need. This ecological relationship has been studied intensively in the western North Atlantic.

Entanglement in fishing gear

Entanglement in fishing gear is a major source of injury and mortality for the North Atlantic Right Whale in western North Atlantic. The right whales in the Atlantic get entangled in gillnets and lines connected to crab and lobster pots. There is an enormous amount of fishing in the Bering Sea and the Gulf of Alaska, however, there have been no records of entanglement of right whales in these areas. However, in the eastern Bering Sea this fishing gear is deployed in nearshore waters, areas "not associated and generally not overlapping with known North Pacific right whale distribution." Pot fisheries occur in offshore waters, but are often deployed in winter when right whales are not known to be present.[6]

In the Sea of Okhotsk entanglement in fishing gear may be a more significant problem. The fishing of concern are both deep-water crab traps and Japanese pelagic driftnet gear for salmon. Right whales have been found: alive but entangled in or wounded by crab net gear (2003 and 1996), dead from entanglement in unspecified gear (September 1995), dead from entanglement in Japanese drift net (October 1994), and alive with fishing gear wrapped on the tail flukes (August 1992).[12][46]

Ship collisions

Collisions with commercial ships is the greatest threat to right whales in the North Atlantic. Both the summer feeding ranges and winter calving grounds are located in some of the busiest shipping channels in the western North Atlantic.[6] However, the North Pacific Right Whale does not seem to be spending much time near shipping channels. There is almost no published data that identifies or quantifies ship collisions or entanglement as substantial mortality factors for the North Pacific Right Whale.[6]

Ship Noise

In its 2006 Status Review, NMFS reviews the scientific studies on the effects of noise pollution on marine mammals and concludes: "In general, the impact of noise from shipping or industrial activities on the communication, behavior and distribution of right whales remains unknown."[6]

Whaling

The illegal catch of more than 500 right whales by Soviet whalers in the 1960s dramatically increased the risk of extinction of this species. Russia no longer hunts whales commercially in the North Pacific. In the 1970s, four right whales were taken by Chinese and Korean whalers. However, since then, there is no record of any right whales having been taken by whalers.[12]

Laws & regulations

International laws on whaling and whale products

The plight of the right whale populations was recognized relatively early. Hunting right whales was prohibited in the first international whaling treaty, the International Convention for the Regulation of Whaling signed in 1931. The treaty did not come into effect until 1935. Although the United States, Canada and Mexico ratified the treaty, Japan and the Soviet Union did not, and thus were not bound by its prohibition. Attempts to bring all the major whaling nations under an international regime stalled and then were deferred until after the end of World War II.[47]

After the war ended, in 1946 all the major whaling countries signed the Convention on the International Regulation of Whaling which established the International Whaling Commission (IWC). This treaty came into effect in 1949. The Commission's initial regulations barred the taking of any right whales. Currently, the IWC classifies the North Pacific Right Whale a "Protection Stock" on which no commercial whaling is permitted.[48]

The International Whaling Commission sets maximum annual quotas for "commercial" whaling—zero in the case of right whales. However, the underlying Convention explicitly authorized member countries to issue to their own whalers permits to take whales for scientific research.[49] This scientific research exemption/loophole has recently become a heated, controversial subject as Japan has been testing the limits of how big this exemption is and what constitutes scientific research justifying such a catch in the absence of a commercial quota. Of relevance here is that in 1955, the Soviet Union granted itself permits to kill 10 right whales, and in 1956 and 1958 the Japanese granted themselves scientific permits to kill 13 right whales. It is from these 23 animals that most of the published data on North Pacific Right Whale morphology and reproductive biology comes. No further scientific permits have been issued by any country for the taking of right whales.[47]

During the 1960s, the International Whaling Commission did not place international observers on whaling ships to record any infractions. Whaling nations were expected to monitor their own nation's whalers to achieve compliance. This trust was abused enormously by the Soviet Union whose whalers were directed to capture thousands of protected Blue Whales, Humpback Whales and right whales around the world. In the North Pacific, it was revealed in 2001 that between then and 1963, Soviet whalers had killed 372 right whales in the eastern North Pacific and an additional 126 whales in the Sea of Okhotsk.[12] The Russians have since stopped engaging in pelagic whaling.

All right whales (Eubalaena spp.) are listed in Appendix I to the Convention on International Trade in Endangered Species (CITES). As such, trade in such species for commercial purposes is banned.

National laws

United States laws

In the United States, the International Whaling Commission's ban on hunting right whales is implemented pursuant to the Whaling Convention Act 16 U.S.C. § 916 et seq.. Jurisdiction over management of whales is held by the National Marine Fisheries Service (NMFS) of the Department of Commerce.

Under the Endangered Species Act, the North Pacific right whales is listed as "endangered".[50] Under the Marine Mammal Protection Act, all right whales, including the North Pacific Right Whale, were determined to be "depleted" in 1973 and remain so classified.

Critical habitat
History
Critical Habitat for North Pacific Right Whale

On 4 October 2000, the Center for Biological Diversity petitioned the National Marine Fisheries Service (NMFS) to designate a critical habitat for the North Pacific Right Whale, asserting that the southeast Bering Sea shelf from 55-60°N should be considered critical habitat. On 20 February 2002, NMFS determined to not designate critical habitat for the North Pacific Right Whale (67 FR 7660) at that time, arguing that existing information available was not sufficient to determine what area was critical to the whale's survival. The Center for Biological Diversity challenged NMFS' determination in court, and in June 2005, a federal judge found NMFS's determination invalid and directed the agency to publish a proposed rule designating a critical habitat. In 2006, NMFS issued a final rule designating two areas as Northern Right Whale critical habitats, one in the Gulf of Alaska south of Kodiak Island and one in the southeast Bering Sea (71 FR 38277, 6 July 2006). When NMFS determined the Northern Right Whale should be split into E. glacialis and E. japonica, it had to reissue the rule defining critical habitat, modified to refer to the North Pacific Right Whale. (73 FR 19000, April 8, 200).[51][52]

Why these specific areas

Under the Endangered Species Act, to be designated as a critical habitat, an area must contain one or more "primary constituent elements" (PCEs) that are essential to the conservation of the species.[53] In the case of the North Pacific right whale the NMFS identified as PCEs:

  1. species of large zooplankton in areas where right whale[s] are known or believed to feed, in particular the copepods Calanus marshallae, Neocalanus cristatus, and Thysanoessa raschii whose high lipid content, and occurrence in this area makes it a preferred prey item of right whales.[54]
  2. physical concentrating mechanisms that are the products of physical and biological oceanography features that aggregate the prey species into densities high enough to support efficient feeding by right whales. Rather than measure these oceanographic features directly, NMFS used the repeated sightings of right whales in the same small geographic area in spring and syummer as a proxy for presuming that the underlying PCEs were present.[55]
Conservation impact

The areas designated as critical habitats support extensive and multi-species commercial fisheries for pollock, flatfish, cod, various crabs and other resources (but not salmon). NMFS found that these fisheries do not threaten the continued availability of the PCEs to right whales. NMFS did find that the zooplankton PCE was vulnerable to oil spills and discharges from oil and gas drilling and production, and protection for the right whale may require special protection through such measures as conditioning federal permits or authorizations through special operational constraints.[56]

Once critical habistat has been designated, that each federal agency must consult with NMFS to ensure that any action authorized, funded or carried out by such agency is not likely to result in the destruction or adverse modification of critical habitat.

Recovery plans

Pursuant to the Endangered Species Act, the U.S. National Marine Fisheries Service has issued a Final Recovery Plan for the North Atlantic Right Whale E. glacialis, but none for the North Pacific Right Whale. The NMFS created a Northern Right Whale Recovery Team in July 1987. After public review of a Draft Recovery Plan, in December 1991, NMFS approved the Final Recovery Plan for the Northern Right Whale (including both the North Atlantic and North Pacific Right Whales). (The factors affecting the continued survival of the Northern Right Whale identified in that plan are discussed above in the section on threats to the continued survival of the North Pacific Right Whales)

After the Northern Right Whale was split into two species, NMFS updated the 1991 Recovery Plan with respect to North Atlantic Right Whale and issued a revised.[57]

According to NMFS, a separate recovery plan is being developed for the North Pacific Right Whale.[58] In December 2006, NMFS issued a status review.[59]

Canadian laws

In Canada, some right whales had been caught in the early 20th century from whaling stations off northern Vancouver Island. However, there have been no sightings of right whales in Canadian waters since the large Soviet illegal kill in the 1960s, much of which took place in the eastern Bering Sea. Neverthelss, in 2003, Fisheries & Oceans Canada issued a National Recovery Strategy for the North Pacific Right Whale (Eubalaena japonica) in Pacific Canadian Waters. In February 2007, Fisheries & Oceans released a draft plan.[60]

History of whaling

Whaling pre-1835

The catch of right whales before 1835 was so small, it probably had no significant effect on the population size. In the North Atlantic, shore-based whalers had hunted right whales since at least the 11th century[61] and the population was so low by the mid-19th century that the famous Scottish whaler Scoresby never saw a right whale.[62] In contrast, the shore-based whaling for right whales in the North Pacific was of very limited scope.

In Japan, hunting for right whales dates back at least to the 16th century, although stranded whales had been utilized for centuries before then. In 1675, Yoriharu Wada invented a new method of whaling. Whales were entangled in nets, and then harpooned. Initially the nets were made of straw, but later made of the stronger hemp. Many small boats were needed for the hunt. One hunting group consisted of 15-20 Seko-bune or beater boats for driving and killing whales, 6 Ami-bune or netting boats and 4 Mosso-bune or tug bots, for a total of 35-30 boats with crews of about 400. In addition to right whales, the whalers took Gray Whales and Humpback Whales.[34]

Right whales were taken in this fishery in two regions of Japan: the south coast (Mie, Wakayama and Kochi prefectures) on the east coasts, and the waters north of the prefectures from Kyoto to Yamaguchi and to the west of Kyushu which hunted in the Sea of Japan. Off the south coast of Japan, right whales were taken in a season lasting from winter to spring. Catches of right whales in Kochi prefecture in the Pacific Ocean between 1800-1835 totaled 259 whales. Catches at Ine on the Sea of Japan during the periods 1700-1850 averaged less than 1 right whale per year. Catches at Kawaijiri also on the Sea of Japan were about 2 right whales per year from 1699-1818.[34]

A few Native American tribes hunted whales in the North Pacific. Their catches were much lower than the Japanese. The Inuit along the western and northwestern coasts of Alaska have hunted whales for centuries. However, their prey has been the Bowhead Whale, and occasionally the Gray Whale. The areas they hunted were at or beyond the northern limits of the right whale's range in the Bering Sea.

The Aleuts hunted the Gray and North Pacific Right Whales along the Aleutian Islands and the Alaska peninsula. The Aleuts hunted using poisoned harpoons. The amount of the Aleut catch of right whales is unknown, but was likely to be no more than a few whales at year.[37][63]

The Nootka, Makah, Quilleute and Auinault tribes of Vancouver Island and the coast of Washington were also skilled whalers. They hunted considerable numbers of the Gray and humpback Whales. Right whales were extremely rare in their catches.[37]

Pelagic whaling 1835-1850

Whalers retrieving the baleen ("whalebone") from a right whale. (NOAA Photo library)

The North Pacific was the portion of the right whale's range furthest from the markets for whale products in New England and Europe. During the open-boat era of open ocean whaling, the whalers, mainly American ships, hunted in the nearest ranges first. As the fleet increased in size and scope, they spread to the eastern North Atlantic and, by the 1770s, the South Atlantic. Following the lead of the British, the first American vessels were sent to the South Pacific in 1791, and by the end of the decade the former's vessels had reached the eastern North Pacific. By the 1820s, the whalers had started to use Lahaina, Hawaii as a base for hunting Sperm Whales.

In 1835, the French whaleship Gange ventured north of 50°N and caught the first right whale by a pelagic whaler in the North Pacific. Word quickly spread among the other whalers. The number of whaleships in the North Pacific north of 50°N hunting right whales increased from 2 in 1839 to 108 in 1843 and 292 in 1846. During the height of pelagic whaling in the North Pacific, approximately 10% of the fleet was non-American, primarily French.[23][64]

It has been estimated that the total mortality in this fishery is in the range of 26,500-37,000 animals during the period 1839-1909. In the single decade of 1840-49, between 21,000-30,000 right whales may have been killed in the North Pacific, Sea of Okhotsk and Bering Sea, representing about 80% of the northern right whales killed in this region during the period 1839-1909.[8]

In 1848, a whaler ventured through the Bering Straits and discovered unexploited populations of Bowhead Whales. Being more abundant, easier to capture, and yielding far more baleen, the majority of whalers rapidly switched from hunting right whales to hunting Bowheads. Since Bowheads occur north of the range of right whales in the North Pacific, the hunting pressure on right whales declined rapidly.[64]

Whaling 1850-1960s

After the whalers discovered the bowhead whales north of the Bering Strait, they quickly turned their ships to them, thereby leaving the more southern range of right whale. In the decade between 1850-1859, the total catch of right whales in the North Pacific, Bering Sea and Sea of Okhotsk dropped to 3,000-4,000 animals, one-sixth of the level in the previous decade. Between 1860-1870, it dropped to 1,000 animals. By the end of the 19th century, the catch by pelagic whalers was averaging less than 10 right whales per year.[8]

In the late 19th century, the development of steam-driven whale catchers and the explosive harpoon opened up new opportunities for whalers. Species previously too swift to hunt commercially could now be caught—Blue and Fin Whales. Small coastal whaling operations opened on the west coast in California, Oregon, and Washington, British Columbia, and in the Aleutian Islands and in southeast Alaska, and in the Kuril Islands in the west. The whale catchers would hunt the whales by day then tow them back to the station for flensing, thus limiting their operation to a fairly small area around the whaling stations. Although the main focus of these whaling operations was on Blue, Humpback, Fin and Sperm Whales, right whales were taken when they were encountered. A few right whales were recorded in catches from these stations.[12][37][64][65] A close-up photo of a North Pacific Right Whale taken at the Kyuquot whaling station, British Columbia in 1918 can be seen here.

The development of steam-driven whale catchers and the new "factory ships" which allowed processing of the carcasses while at sea also transformed pelagic whaling in the North Pacific. Right whales continued to be taken by these whalers, although uncommonly due to their rarity. Japan continued hunting right whales through the beginning of World War II. At the end of the war, General MacArthur, head of Allied occupation forces, encouraged the Japanese to resume whaling as a means of feeding their hungry population. However, after World War II, Japan was now a member of the International Whaling Commission which barred the hunting of right whales. Except for 13 whales killed under "scientific permits" Japan issued its whalers in accordance with IWC rules, Japanese whalers have honored the prohibition on taking right whales.

Illegal Soviet whaling in the 1960s

The same cannot be said for Soviet whalers. In the 1960s, Soviet whalers had no international observers on board, and no conservation groups following them at sea. The Soviet whalers apparently honored the prohibition on taking right whales until 1963, by which time populations of humpback, blue and fin whales were getting harder to find in the North Pacific. Between 1963-67, the Soviet whalers ignored the ban on hunting right whales, apparently killed every right whale they found, and then filed fraudulent reports with the Bureau of International Whaling Statistics and the International Whaling Commission. During these five years, the Soviets killed 372 right whales in the Bering Sea and eastern North Pacific, an additional 126 right whales in the Sea of Okhotsk between 1963-67 and another 10 more in the Kuril Islands in 1971. In their reports, the Soviets admitted killing only one right whale, by accident. The Russian biologists who had been on the whaling ships were prohibited from examining the carcasses or taking any biological measurements of these whales. Nevertheless, the biologists kept their own records of what the whalers actually caught, then kept these records secret for more than two decades.[66] After the collapse of the Soviet government, the new Russian government released the true catch data.[12]

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