Report on Marine Mammal Unusual Mortality Event UMESE0501Sp: Multispecies Mass Stranding of Pilot Whales (Globicephala macrorhynchus), Minke Whale (Balaenoptera acutorostrata), and Dwarf Sperm Whales (Kogia sima) in North Carolina on 15-16 January 2005

On 15-16 January 2005, three offshore species of cetaceans (33 short-finned pilot whales, Globicephala macrorhynchus, one minke whale, Balaenoptera acutorostrata, and two dwarf sperm whales, Kogia sima) stranded alive on the beaches of North Carolina. The pilot whales stranded near Oregon Inlet, the minke whale in northern North Carolina, and the dwarf sperm whales near Cape Hatteras. Live strandings of three species in one weekend was unique in North Carolina and qualified as an Unusual Mortality Event. Gross necropsies were conducted on 16-17 January 2005 on 27 pilot whales, two dwarf sperm whales, and the minke whale. Samples were collected for clinical pathology, parasitology, gross pathology, histopathology, microbiology and serology. There was variation in the number of animals sampled for each collection type, however, due to carcasses washing off the beach or degradation in carcass condition during the course of the response. Comprehensive histologic examination was conducted on 16 pilot whales, both dwarf sperm whales, and the minke whale. Limited organ or only head tissue suites were obtained from nine pilot whales. Histologic examination of tissues began in February 2005 and concluded in December 2005 when final sampling was concluded. Neither the pilot whales nor dwarf sperm whales were emaciated although none had recently ingested prey in their stomachs. The minke whale was emaciated; it was likely a dependent calf that became separated from the female. Most serum biochemistry abnormalities appear to have resulted from the stranding and indicated deteriorating condition from being on land for an extended period. Three pilot whales had clinical evidence of pre-existing systemic inflammation, which was supported by histopathologic findings. Although gross and histologic lesions involving all organ systems were noted, consistent lesions were not observed across species. Verminous pterygoid sinusitis and healed fishery interactions were seen in pilot whales but neither of these changes were causes of debilitation or death. In three pilot whales and one dwarf sperm whale there was evidence of clinically significant disease in postcranial tissues which led to chronic debilitation. Cardiovascular disease was present in one pilot whale and one dwarf sperm whale; musculoskeletal disease and intra-abdominal granulomas were present in two pilot whales. These lesions were possible, but not definitive, causal factors in the stranding. Remaining lesions were incidental or post-stranding. The minke whale and three of five tested pilot whales had positive morbillivirus titers (≥1:8 with one at >1:256), but there was no histologic evidence of active viral infection. Parasites (nematodes, cestodes, and trematodes) were collected from 26 pilot whales and two dwarf sperm whales. Sites of collection included stomach, nasal/pterygoid, peribullar sinuses, blubber, and abdominal cavity. Parasite species, locations and loads were within normal limits for free-ranging cetaceans and were not considered causative for the stranding event. Gas emboli lesions which were considered consistent with or diagnostic of sonarassociated strandings of beaked whales or small cetaceans were not found in the whales stranded as part of UMESE0501Sp. Twenty-five heads were examined with nine specific anatomic locations of interest: extramandibular fat, intramandibular fat, auditory meatus, peribullar acoustic fat, peribullar soft tissue, peribullar sinus, pterygoid sinus, melon, and brain. The common finding in all examined heads was verminous pterygoid sinusitis. Intramandibular adipose tissue reddening, typically adjacent to the vascular plexus, was observed in some individuals and could represent localized hemorrhage resulting from vascular rete rupture, hypostatic congestion, or erythrocyte rupture during the freeze/thaw cycle. One cetacean had peracute to acute subdural hemorrhage that likely occurred from thrashing on the beach post-stranding, although its occurrence prior to stranding cannot be excluded. Information provided to NMFS by the U.S. Navy indicated routine tactical mid-frequency sonar operations from individual surface vessels over relatively short durations and small spatial scales within the area and time period investigated. No marine mammals were detected by marine mammal observers on operational vessels; standard operating procedure for surface naval vessels operating mid-frequency sonar is the use of trained visual lookouts using high-powered binoculars. Sound propagation modeling using information provided to NMFS indicated that acoustic conditions in the vicinity likely depended heavily on position of the receivers (e.g., range, bearing, depth) relative to that of the sources. Absent explicit information on the location of animals meant that it was not possible to estimate received acoustic exposures from active sonar transmissions. Nonetheless, the event was associated in time and space with naval activity using mid-frequency active sonar. It also had a number of features in common (e.g., the “atypical” distribution of strandings involving multiple offshore species, all stranding alive, and without evidence of common infectious or other disease process) with other sonar-related cetacean mass stranding events. Given that this event was the only stranding of offshore species to occur within a 2-3 day period in the region on record (i.e., a very rare event), and given the occurrence of the event simultaneously in time and space with a naval exercise using active sonar, the association between the naval sonar activity and the location and timing of the event could be a causal rather than a coincidental relationship. However, evidence supporting a definitive association is lacking, and, in particular, there are differences in operational/environmental characteristics between this event and previous events where sonar has apparently played a role in marine mammal strandings. This does not preclude behavorial avoidance of noise exposure. No harmful algal blooms were present along the Atlantic coast south of the Chesapeake Bay during the months prior to the event. Environmental conditions, including strong winds, changes in upwelling- to downwelling-favorable conditions, and gently sloping bathymetry, were consistent with conditions which have been correlated with other mass strandings. In summary, we did not find commonality in gross and histologic lesions that would indicate a single cause for this stranding event. Three pilot whales and one dwarf sperm whale had debilitating conditions identified that could have contributed to stranding, one pilot whale had a debilitating condition (subdural hemorrhage) that could have been present prior to or resulting from stranding. While the pilot and dwarf sperm whale strandings may have had a common cause, the minke whale stranding was probably just coincidental. On the basis of examination of physical evidence in the affected whales, however, we cannot definitively conclude that there was or was not a causal link between anthropogenic sonar activity or environmental conditions (or a combination of these factors) and the strandings. Overall, the cause of UMESE0501Sp in North Carolina is not and likely will not be definitively known. (PDF contains 240 pages)

Cryopreservation of sperm of common carp, Cyprinus carpio and silver barb, Barbonymus gonionotus for genetically improved seed production

Experiments were conducted to develop and standardize the protocols for cryopreservation of sperm of common carp, Cyprinus carpio and also for using the cryopreserved sperm for fertilization of eggs. Nine extender solutions as Alsever's solution, kurokura-1, kurokura-2, urea egg-yolk, egg-yolk citrate, 0.6% glucose, 0.9% NaCl, Ma and Mb, and five cryoprotectants namely ethanol, methanol, dimethylsulfoxide (DMSO), dimethylamine (DMA) and glycerol were tested. The cryoprotectants were mixed at 10% concentration of the extenders (v/v) to make the cryodiluents. Milt and cryodiluents were mixed at a ratio of 1:9 for Alsever's solution, kurokura-1, kurokura-2, 0.6% glucose and 0.9% NaCl, 1:4 for urea egg-yolk, egg-yolk citrate, Ma and Mb. Among the cryodiluents Alsever's solution mixed with either ethanol or methanol was found to be suitable and it produced more than 90% and 80% spermatozoan motility at equilibrium and post-thaw periods, respectively. Kurokura-1 and kurokura-2 when mixed with the same cryoprotectants showed good spermatozoan motility at equilibrium period (80-90%) but the motility was reduced (30-55%) at post-thaw state. Other extenders did not produce acceptable sperm-motility and in some cases the frozen milt became clotted. Different dilution ratios (1:1, 1:2, 1:4, 1:5, 1:7, 1:9, 1:12, 1:15, 1:20) were formulated for obtaining a suitable milt dilution, the dilution ratio of 1: 9 (milt : cryodiluent) demonstrated the highest post-thaw spermatozoan motility (80%) in Alserver's solution. The optimum concentration of cryoprotectants in the cryodiluents was determined, 10% concentration level was found to be effective to produce the highest number of spermatozoan motility in comparison to the other concentrations (5%, 15%, 20% 30%). Sperm preserved with the cryodiluent Alsever's solution along with either methanol or ethanol was found to be effective to fertilize eggs and produce hatchlings. The hatching rates ranged between 1.48% and 14.76%, compare to control. The fish produced through use of cryopreserved sperm and normal sperm were found to grow well and no significant (P<0.05) growth difference was observed between them. In case of silver barb, Barbonymus gonionotus, sperm tested against six extenders such as egg-yolk citrate, urea-egg-yolk, kurokura-1, kurokura-2, 0.9% NaCl and modified fish ringer (MFR) solution. Cryoprotectants used were the same as those of C. carpio. Milt was diluted with the cryodiluent at a ratio of 1:4 for egg-yolk citrate and urea-egg-yolk, 1:5 for kurokura-1 and 1:9 for 0.9% NaCl, MFR and kurokura-2. The cryoprotectant concentration was maintained at 10% of the extender (v/v) in all the cases. Among the extenders, egg-yolk citrate and urea-egg-yolk mixed with 10% DMSO, methanol and ethanol produced 50% post-thaw spermatozoan motility, whereas DMA and glycerol provided only 10% motility. Trials on milt dilution ratio and cryoprotectant concentration are being conducted. Fertilization trials are also underway.

Cruise Report 51-S-1 of N.B. Scofield: Number S-21 of the Cooperative Sardine Research Program

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Cephalopods from the stomachs of sperm whales taken off California

Cephalopod remains (beaks, bodies, and parts of bodies) were collected from the stomachs of 157 sperm whales (Physeter macrocephalus) taken off central California (lat. 37°-39°N). At least 24 species representing 14 families were identified. Frequencies of occurrence of the six most numerous taxa were Moroteuthis robusta 72.0%, Gonatopsis borealis 66.2%, Histioteuthis dofleini 36.9%, Galiteuthis spp. (including G. phyllura and G. pacifica) 36.3%, Octopoteuthis deletron 35.0%, and Vampyroteuthis infernalis 27.4%. One find of two Mesonychoteuthis hamiltoni beaks strongly suggests transequatorial migration by one large male sperm whale. (PDF file contains 18 pages.)

Estimation of the number of purse-seiner sets on tuna associated with dolphins in the Eastern Pacific Ocean during 1959-1980

ENGLISH: Annual estimates of the number of purse-seine sets made on tunas associated with dolphins are needed to estimate the total number of dolphins killed incidentally by the eastern Pacific tuna fishery. The most complete source of data, the Inter-American Tropical Tuna Commission's logbook data base, was used in this study. In the logbook data base, most sets are identified as being either associated with dolphins or not associated with dolphins. Some sets are not identified in this respect. However, the number of these unidentified sets which were associated with dolphins have been estimated by stratifying the logbook data according to whether or not any tuna were caught, whether or not the nearest identified set was associated with dolphins, and the distance to the nearest identified set. Most of the unidentified sets fell in strata characterized by a proportion of sets on tuna associated with dolphins that was lower than the overall unstratified proportion. Landings data were used to estimate the number of sets on tunas associated with dolphins from fishing trips not included in the logbook data base. SPANISH: Se necesitan las estimaciones anuales de la cantidad de lances realizados sobre atunes asociados con delfines para calcular todo el número de delfines muertos accidentalmente en la pesca atunera del Pacífico oriental. Se empleó en este estudio la fuente más completa-los datos de la Comisión Interamericana del Atún Tropical, proveniente de los cuadernos de bitácora. En éstos, la mayoría de los lances han sido identificados ya sea como asociados o no asociados con delfines. Algunos de los lances no han sido identificados a este respecto. Sin embargo, se ha estimado el número de estos lances asociados con delfines que no se habían identificado, al estratificar los datos de bitácora de acuerdo a si se había o no capturado atún, a si el lance identificado más próximo era o no un lance asociado con delfines y al averiguar la distancia del lance identificado más cercano. La mayoría de los lances sin identificar se colocan en los estratos caracterizados por una proporción de lances sobre atunes asociados con delfines, inferior a la proporción general sin estratificar. Se usaron los datos de los desembarques para calcular la cantidad de lances sobre atunes asociados con delfines en viajes pesqueros que no fueron incluídos en la base de los datos de bitácora. (PDF contains 73 pages.)

Influence of number of valves on catch composition of a fishing pot trap (Lege) in River Rima, north western Nigeria

Three types of prototype (Lege) traps with different numbers of entrance valves were evaluated in River Rima, north western Nigeria. The traps contained 4,6 and 8 valves, tagged 4-V, 6-V and 8-V respectively. The experiment was carried out in a randomized complete block design with one factor each replicated three times. Data collected on fish diversity, number biomass and sizes were subjected to descriptive statistics and analysis of variance. The results of the catch composition showed close diversity index of 0.86 for 6-V, 0.80 for 8-V and 0.60 for 4-V Lege traps. However, the number (41%) and biomass 48%) of fish caught in the 6-V Lege trap were significantly (P0.05) higher than those caught in the other traps. There was no definite trend in the sizes (length and girth) of fish caught in the traps. On the basis of species diversity, and the number and biomass of fish caught, the 6-V Lege showed preference for adoption than the other two traps. However, further studies are recommended on the appropriate mesh size net for the trap in line with the provisions of fisheries edicts

Influence of number of valves on catch composition of a fishing pot trap (Lege) in River Rima, north western Nigeria

Three types of prototype (Lege) traps with different numbers of entrance valves were evaluated in River Rima, north western Nigeria. The traps contained 4,6 and 8 valves, tagged 4-V, 6-V and 8-V respectively. The experiment was carried out in a randomized complete block design with one factor each replicated three times. Data collected on fish diversity, number, biomass and sizes were subjected to descriptive statistics and analysis of variance. The results of the catch composition showed close diversity index of 0.86 for 6-V, 0.80 for 8-V and 0.60 for 4-V Lege traps. However, the number (41%) and biomass (48%) of fish caught in the 6-V Lege trap were significantly (P<0.05) higher than those caught in the other traps. There was no definite trend in the sizes (length and girth) of fish caught in the traps. On the basis of species diversity, and the number and biomass of fish caught, the 6-V Lege showed preference for adoption than the other two traps. However, further studies are recommended on the appropriate mesh size net for the trap in line with the provisions of fisheries edicts

Radioautographic method of determination of number of bacteria in water-bodies [Translation from: Informatsionnyi Byulleten Biologiya Vnutrennikh Vod No.26, 65-67, 1975]

The radioautographic method of determination of the number of autotrophic microorganisms was initially suggested for counting methane-oxidizing bacteria. With the help of this method colonies of hydrogen-oxidizing bacteria are differentiated even more clearly from heterotrophic. Under laboratory conditions it was shown that colonies grown on membrane filters from a pure culture of thionic bacteria on a nutrient medium with radio- active carbonate, give better prints on film. This method was tested by the authors for determining the number of these bacteria in the meromictic Lake Vae de San Juan during the expedition to Cuba in the summer of 1973. The study showed that that the thionic bacteria are found throughout the pelagial. It proved that the thionic bacteria can be well considered in water-bodies by the radioautographic method.

On the number of generations of tendipes in collective ponds in Kuibyshchevskoi district [Translation from: C.R. Acad.Sci. U.R.S.S. 95, 1113-1115, 1954]

Three ponds were chosen for this study. The two lower ones were of 2 - 4 hectares in area, the depth of the littoral zone was 2.5 - 3 metres at the time of maximum flooding and the mud which covered the floor of the ponds was homogeneous and autochthonous in nature with very few vegetable remnants. The ponds which were originally set up in 1950. were intended for water supply and populated with Crucian Carp (for human consumption). A survey was done in the ponds in order to establish number and biomass of Tendipes semireductus. The author concludes that in these ponds T.semireductus has 2-3 generations per year.

A coarse fish close season on canals. Paper in evidence to the review of fisheries policy and legislation. Paper number: EA-12

This paper gives the results of the Environment Agency's research into the canal close season to the Salmon and Freshwater Fisheries Review Group. It presents the findings of the research, explains why the research was undertaken and how it relates to the Agency's duties. The background for this report includes that angling representative bodies have long argued that the existing situation in which somecanals have a close season and others do not, is unsatisfactory.

Soviet Illegal Whaling: The Devil and the Details

In 1948, the U.S.S.R. began a global campaign of illegal whaling that lasted for three decades and, together with the poorly managed “legal” whaling of other nations, seriously depleted whale populations. Although the general story of this whaling has been told and the catch record largely corrected for the Southern Hemisphere, major gaps remain in the North Pacific. Furthermore, little attention has been paid to the details of this system or its economic context. Using interviews with former Soviet whalers and biologists as well as previously unavailable reports and other material in Russian, our objective is to describe how the Soviet whaling industry was structured and how it worked, from the largest scale of state industrial planning down to the daily details of the ways in which whales were caught and processed, and how data sent to the Bureau of International Whaling Statistics were falsified. Soviet whaling began with the factory ship Aleut in 1933, but by 1963 the industry had a truly global reach, with seven factory fleets (some very large). Catches were driven by a state planning system that set annual production targets. The system gave bonuses and honors only when these were met or exceeded, and it frequently increased the following year’s targets to match the previous year’s production; scientific estimates of the sustainability of the resource were largely ignored. Inevitably, this system led to whale populations being rapidly reduced. Furthermore, productivity was measured in gross output (weights of whales caught), regardless of whether carcasses were sound or rotten, or whether much of the animal was unutilized. Whaling fleets employed numerous people, including women (in one case as the captain of a catcher boat). Because of relatively high salaries and the potential for bonuses, positions in the whaling industry were much sought-after. Catching and processing of whales was highly mechanized and became increasingly efficient as the industry gained more experience. In a single day, the largest factory ships could process up to 200 small sperm whales, Physeter macrocephalus; 100 humpback whales, Megaptera novaeangliae; or 30–35 pygmy blue whales, Balaenoptera musculus brevicauda. However, processing of many animals involved nothing more than stripping the carcass of blubber and then discarding the rest. Until 1952, the main product was whale oil; only later was baleen whale meat regularly utilized. Falsified data on catches were routinely submitted to the Bureau of International Whaling Statistics, but the true catch and biological data were preserved for research and administrative purposes. National inspectors were present at most times, but, with occasional exceptions, they worked primarily to assist fulfillment of plan targets and routinely ignored the illegal nature of many catches. In all, during 40 years of whaling in the Antarctic, the U.S.S.R. reported 185,778 whales taken but at least 338,336 were actually killed. Data for the North Pacific are currently incomplete, but from provisional data we estimate that at least 30,000 whales were killed illegally in this ocean. Overall, we judge that, worldwide, the U.S.S.R. killed approximately 180,000 whales illegally and caused a number of population crashes. Finally, we note that Soviet illegal catches continued after 1972 despite the presence of international observers on factory fleets.

An atlas of reproductive development in rockfishes, genus Sebastes

The genus Sebastes consists of over 100 fish species, all of which are viviparous and long-lived. Previous studies have presented schemes on the reproductive biology of a single targeted species of the genus Sebastes, but all appear to possess a similar reproductive biology as evidenced by this and other studies. This atlas stages major events during spermatogenesis, oogenesis, and embryogenesis, including atresia, in six species of Sebastes (S. alutus, S. elongatus, S. helvomaculatus, S. polyspinis, S. proriger, and S. zacentrus). Our study suggests that the male reproductive cycle of Sebastes is characterized by 11 phases of testicular development, with 10 stages of sperm development and 1 stage of spermatozoa atresia. Ovarian development was divided into 12 phases, with 10 stages of oocyte development, 1 stage of embryonic development, and 1 stage of oocyte atresia. Embryonic development up to parturition was divided into 33 stages following the research of Yamada and Kusakari (1991). Reproductive development of all six species examined followed the developmental classifications listed above which may apply to all species of Sebastes regardless of the number of broods produced annually. Multiple brooders vary in that not all ova are fertilized and progress to embryos; a proportion of ova are arrested at the pre-vitellogenic stage. Reproductive stage examples shown in this atlas use S. elongates for spermatic development, S. proriger for oocyte development, and S. alutus for embryological development, because opportunistic sampling only permitted complete analysis of each respective developmental phase for those species. The results of this study and the proposed reproductive phases complement the recommended scheme submitted by Brown-Peterson et al. (2011), who call for a standardization of terminology for describing reproductive development of fishes.