Whaling as Science

In an open letter published last year in the New York Times, 21 distinguished scientists (including three Nobel laureates) criticized Japan's program of scientific research whaling, noting its poor design and unjustified reliance upon lethal sampling. In a recent Forum article in BioScience, Aron, Burke, and Freeman (2002) castigate the letter's signers and accuse them of meddling in political issues without sufficient knowledge of the science involved in those issues.

Distribution of North Pacific right whales (Eubalaena japonica) as shown by 19th and 20th century whaling catch and sighting records

North Pacific right whales (Eubalaena japonica) were extensively exploited in the 19th century, and their recovery was further retarded (severely so in the eastern population) by illegal Soviet catches in the 20th century, primarily in the 1960s. Monthly plots of right whale sightings and catches from both the 19th and 20th centuries are provided, using data summarized by Scarff (1991, from the whale charts of Matthew Fontaine Maury) and Brownell et al. (2001), respectively. Right whales had an extensive offshore distribution in the 19th century, and were common in areas (such as the Gulf of Alaska and Sea of Japan) where few or no right whales occur today. Seasonal movements of right whales are apparent in the data, although to some extent these reflect survey and whaling effort. That said, these seasonal movements indicate a general northward migration in spring from lower latitudes, and major concentrations above 40°N in summer. Sightings diminished and occurred further south in autumn, and few animals were recorded anywhere in winter. These north-south migratory movements support the hypothesis of two largely discrete populations of right whales in the eastern and western North Pacific. Overall, these analyses confirm that the size and range of the right whale population is now considerably diminished in the North Pacific relative to the situation during the peak period of whaling for this species in the 19th century. For management purposes, new surveys are urgently required to establish the present distribution of this species; existing data suggest that the Bering Sea, the Gulf of Alaska, the Okhotsk Sea, the Kuril Islands and the coast of Kamchatka are the areas with the greatest likelihood of finding right whales today.

Baleen Whales: Conservation Issues and The Status Of The Most Endangered Populations

Most species of baleen whales were subject to intensive overexploitation by commercial whaling in this and previous centuries, and many populations were reduced to small fractions of their original sizes. Here, we review the status of baleen whale stocks, with an emphasis on those that are known or thought to be critically endangered. Current data suggest that, of the various threats potentially affecting baleen whales, only entanglement in fishing gear and ship strikes may be significant at the population level, and then only in those populations which are already at critically low abundance. The impact of some problems (vessel harassment, and commercial or aboriginal whaling) is at present probably minor. For others (contaminants, habitat degradation, disease), existing data either indicate no immediate cause for concern, or are insufficient to permit an assessment. While the prospect for many baleen whales appears good, there are notable exceptions; populations that are of greatest concern are those suffering from low abundance and associated problems, including (in some cases) anthropogenic mortality. These include: all Northern Right Whales Eubalaena glacialis, Bowhead Whales Balaena mysticetus of the Okhotsk Sea and various eastern Arctic populations, western Gray Whales Eschrichtius robustus, and probably many Blue Whale Balaenoptera musculus populations. We review the status of these populations and, where known, the issues potentially affecting their recovery. Although Humpback Whales Megaptera novaeangliae and Southern Right Whales Eubalaena australis were also heavily exploited by whaling, existing data indicate strong recovery in most studied populations of these species.

The whaling issue: Conservation, confusion, and casuistry

Morishita’s “multiple analysis”of the whaling issue [Morishita J. Multiple analysis of the whaling issue: Understanding the dispute by a matrix. Marine Policy 2006;30:802–8] is essentially a restatement of the Government of Japan’s whaling policy, which confuses the issue through selective use of data, unsubstantiated facts, and the vilification of opposing perspectives. Here, we deconstruct the major problems with Morishita’s article and provide an alternative view of the whaling dispute. For many people in this debate, the issue is not that some whales are not abundant, but that the whaling industry cannot be trusted to regulate itself or to honestly assess the status of potentially exploitable populations. This suspicion has its origin in Japan’s poor use of science, its often implausible stock assessments, its insistence that culling is an appropriate way to manage marine mammal populations, and its relatively recent falsification of whaling and fisheries catch data combined with a refusal to accept true transparency in catch and market monitoring. Japanese policy on whaling cannot be viewed in isolation, but is part of a larger framework involving a perceived right to secure unlimited access to global marine resources. Whaling is inextricably tied to the international fisheries agreements on which Japan is strongly dependent; thus, concessions made at the IWC would have potentially serious ramifications in other fora.

Japan’s whaling plan under scrutiny

Eighteen years after initiating scientific whaling in Antarctic waters, Japan presented a new and more ambitious program to the International Whaling Commission (IWC); the proposal was made in early June during the IWC’s annual meeting in Ulsan, Korea. Japan now wishes to more than double its annual catch of Antarctic minke whales (from about 440 to 935), and to expand lethal sampling to include an additional yearly take of 50 humpback and 50 fin whales. Unlike catches for commercial whaling, scientific catches are unregulated. Since 1987, Japan has taken some 6,800 minke whales from Antarctic waters, despite ongoing criticism of the relevance and direction of Japan’s research. The IWC was set up to regulate commercial whaling and to conserve whale populations, under the authority of the 1946 International Convention for the Regulation of Whaling. Following a well-documented failure of management that led to the collapse of most global whale populations, the IWC set a zero quota for commercial whaling (the moratorium). This was made effective from 1986. Norway, the former Soviet Union and Japan initially objected to the moratorium, but Japan withdrew its objection and ceased commercial whaling in 1988.

Recovery Plan for The Blue Whale (Balaenoptera musculus)

Recovery plans identify reasonable actions which are believed to be required to recover and/or protect endangered species. Plans are prepared by the National Marine Fisheries Service (NMFS) and the U.S. Fish and Wildlife Service (FWS) and sometimes with the assistance of recovery teams, contractors, State agencies, and others. This plan was prepared by Randall R. Reeves, Phillip J. Clapham, Robert L. Brownell, Jr., and Gregory K. Silber for NMFS. Recovery plans do not necessarily represent the views nor the official positions or approvals of any individuals or agencies, other than those of NMFS, and they represent the views of NMFS only after they have been approved by the Assistant Administrator for Fisheries. Objectives will only be attained and funds expended contingent upon appropriations, priorities, and other budgetary constraints. Approved recovery plans are subject to modification as dictated by new findings, changes in species status, and the completion of recovery tasks described in the plan.

Whaling dispute continues

Apparently alarmed that an advertisement in Nature referencing the study of Baker and Palumbi (Science 265, 1538; 1994) might lend undeserved credence to the notion that illegal whale products find their way into Japanese markets, Milton Freeman (Nature 376, 11; 1995) reiterates the arguments of the Fisheries Agency of Japan (FAJ) that the study is fundamentally flawed. As Freeman's letter contains several serious errors, we feel obliged to comment.

Differences between Tethered Polyelectrolyte Chains on Bare Mica and Hydrophobically Modified Mica

This study investigates the structures of layers of amphiphilic diblock copolymers of poly(t-butyl styrene)-poly- (styrene sulfonate) (PtBS-PSS) adsorbed on both the bare mica surface (hydrophilic) and an octadecyltriethoxysilane (OTE)-modified mica surface (hydrophobic). When the surface is rendered hydrophobic, the nonsoluble block exhibits stronger interaction with the surface and higher adsorbed masses are achieved. Interaction forces between two such adsorbed layers on both substrates were measured using the surface forces apparatus. The effect of salt concentration (Cs) and molecular weight (N) on the height of the self-assembled layers (L0) was examined in each case. The resulting scaling relationship is in good agreement with predictions of the brush model, L0 ∞ N1.0 in the low-salt limit and L0N-1 ∞ (Cs/σ)-0.32 in the salted regime, when adsorption takes place onto the hydrophobized mica surface. For adsorption on the bare mica surface, L0N-0.7 ∞ Cs -0.17 agrees with the scaling prediction of the sparse tethering model. The results suggest that, on the hydrophilic bare mica surface, the adsorbed amount is not high enough to form a brush structure and only very little intermolecular stretching of the tethered chains occurs; in contrast, the presence of the hydrophobic OTE layer increases the tethering density such that the polyelectrolyte chains adopt a brush conformation.

Historical Observations of Humpback And Blue Whales in the North Atlantic Ocean: Clues to Migratory Routes and Possibly Additional Feeding Grounds

The seasonal distributions of humpback and blue whales (Megaptera novaeangliae and Balaenoptera musculus, respectively) in the North Atlantic Ocean are not fully understood. Although humpbacks have been studied intensively in nearshore or coastal feeding and breeding areas, their migratory movements between these areas have been largely inferred. Blue whales have only been studied intensively along the north shore of the Gulf of St. Lawrence, and their seasonal occurrence and movements elsewhere in the North Atlantic are poorly known. We investigated the historical seasonal distributions of these two species using sighting and catch data extracted from American 18th and 19th century whaling logbooks. These data suggest that humpback whales migrated seasonally from low-latitude calving/ breeding grounds over a protracted period, and that some of them traveled far offshore rather than following coastal routes. Also, at least some humpbacks apparently fed early in the summer west of the Mid-Atlantic Ridge, well south of their known present-day feeding grounds. In assessing the present status of the North Atlantic humpback population, it will be important to determine whether such offshore feeding does in fact occur. Blue whales were present across the southern half of the North Atlantic during the autumn and winter months, and farther north in spring and summer, but we had too few data points to support inferences about these whales’ migratory timing and routes.

Acoustic Detections of Singing Humpback Whales in Deep Waters Off The British Isles

From October 1996 through September 1998, we used bottom-mounted hydrophone arrays to monitor deep-water areas north and west of the British Isles for songs of humpback whales (Megaptera novaeangliae). Singing humpbacks were consistently detected between October and March from the Shetland- Faroe Islands south to waters west of the English Channel. Temporal and geographic patterns of song detections, and movements of individually tracked whales, exhibited a southwesterly trend over this period, but with no corresponding northward trend between April and September. These results, together with a review of historical data from this area, suggest that the offshore waters of the British Isles represent a migration corridor for humpbacks, at least some of which summer in Norwegian (and possibly eastern Icelandic) waters. The migratory destination of the detected animals remains unknown, but the limited data suggest that these whales are bound primarily for the West Indies rather than historical breeding areas off the northwestern coast of Africa. Humpbacks detected in British waters after early to mid- March probably do not undertake a full migration to the tropics. These data provide further evidence that singing is not confined to tropical waters in winter, but occurs commonly on migration even in high latitudes.

A Novel Behavior Observed in Humpback Whales on Wintering Grounds at Abrolhos Bank (Brazil)

We describe a novel behavior, termed “tail-up,” observed in humpback whales (Megaptera novaeangliae) on wintering grounds on Abrolhos Bank, Brazil. The behavior involves the whale positioned vertically in the water column with its tail in the air. Wirh the exception of calves, tail-up was observed in all social classes, and its frequency increased through the end of the season. Tail-ups were recorded in 144 (5.8%) of 2,465 groups of whales observed from a shore station, and in 297 (14.9%) of 1,996 groups observed from vessel surveys; biases in each method suggest that the true frequency lies between these sources. One hundred and fifty-two hours of continuous sampling showed that the duration of tail-up events lasted from a few seconds to 12 min and was longest in groups comprised of a single adult. The maximum duration of a recorded period that consistently included tail-up was 10 h; however, some individuals were observed to engage in the behavior at night and for four consecutive days. Tail-up movement speed did not vary by social class; however, it varied according to wind direction and speed. The characteristics of tail-up that we observed showed that it differed from the descriptions of similar behaviors in other cetacean species. The function of tail-up is unknown, but we suggest that it may be a multifunctional behavior.

Segregation of migration by feeding ground origin in North Atlantic humpback whales (Megaptera novaeangliae)

Results from a large-scale, capture–recapture study of humpback whales Megaptera novaeangliae in the North Atlantic show that migration timing is influenced by feeding ground origin. No significant differences were observed in the number of individuals from any feeding area that were re-sighted in the common breeding area in the West Indies. However, there was a relationship between the proportion (logit transformed) of West Indies sightings and longitude (r2 = 0.97, F1,3 = 98.27, P = 0.0022) suggesting that individuals feeding farther to the east are less likely to winter in the West Indies. A relationship was also detected between sighting date in the West Indies and feeding area. Mean sighting dates in the West Indies for individuals identified in the Gulf of Maine and eastern Canada were significantly earlier than those for animals identified in Greenland, Iceland and Norway (9.97 days, t179 = 3.53, P = 0.00054). There was also evidence for sexual segregation in migration; males were seen earlier on the breeding ground than were females (6.63 days, t105 = 1.98, P = 0.050). This pattern was consistently observed for animals from all feeding areas; a combined model showed a significant effect for both sex (F1 = 5.942, P = 0.017) and feeding area (F3 =4.756, P=0.0038). The temporal difference in occupancy of the West Indies between individuals from different feeding areas, coupled with sexual differences in migratory patterns, presents the possibility that there are reduced mating opportunities between individuals from different high latitude areas.

A New Birth-Interval Approach to Estimating Demographic Parameters of Humpback Whales

A demographic model is developed based on interbirth intervals and is applied to estimate the population growth rate of humpback whales (Megaptera novaeangliae) in the Gulf of Maine. Fecundity rates in this model are based on the probabilities of giving birth at time t after a previous birth and on the probabilities of giving birth first at age x. Maximum likelihood methods are used to estimate these probabilities using sighting data collected for individually identified whales. Female survival rates are estimated from these same sighting data using a modified Jolly–Seber method. The youngest age at first parturition is 5 yr, the estimated mean birth interval is 2.38 yr (SE = 0.10 yr), the estimated noncalf survival rate is 0.960 (SE = 0.008), and the estimated calf survival rate is 0.875 (SE = 0.047). The population growth rate (l) is estimated to be 1.065; its standard error is estimated as 0.012 using a Monte Carlo approach, which simulated sampling from a hypothetical population of whales. The simulation is also used to investigate the bias in estimating birth intervals by previous methods. The approach developed here is applicable to studies of other populations for which individual interbirth intervals can be measured.