Chemical contaminants in juvenile gray whales (Eschrichtius robustus) from a subsistence harvest in Arctic feeding grounds

Gray whales are coastal migratory baleen whales that are benthic feeders. Most of their feeding takes place in the northern Pacific Ocean with opportunistic feeding taking place during their migrations and residence on the breeding grounds. The concentrations of organochlorines and trace elements were determined in tissues and stomach contents of juvenile gray whales that were taken on their Arctic feeding grounds in the western Bering Sea during a Russian subsistence harvest. These concentrations were compared to previously published data for contaminants in gray whales that stranded along the west coast of the US during their northbound migration. Feeding in coastal waters during their migrations may present a risk of exposure to toxic chemicals in some regions. The mean concentration (standard error of the mean, SEM) of Σ PCBs [1400 (130) ng/g, lipid weight] in the blubber of juvenile subsistence whales was significantly lower than the mean level [27 000 (11 000) ng/g, lipid weight] reported previously in juvenile gray whales that stranded in waters off the west coast of the US. Aluminum in stomach contents of the subsistence whales was high compared to other marine mammal species, which is consistent with the ingestion of sediment during feeding. Furthermore, the concentrations of potentially toxic chemicals in tissues were relatively low when compared to the concentrations in tissues of other marine mammals feeding at higher trophic levels. These chemical contaminant data for the subsistence gray whales substantially increase the information available for presumably healthy animals.

Raphidascaris camura sp. n., Hysterothylacium eurycheilum (Olsen) comb. n. and Comments on Heterotyphlum Spaul (Nematoda: Ascaroidea) in Marine Fishes

Raphidascaris camura sp. n. infected the stomach and intestine of Pomatomus saltatrix (type host), from the northern Gulf of Mexico. It is characterized by having the following combination of features: 31 to 40 pairs of preanal papillae, 10 pairs of postanal papillae with the third papilla from the posterior extremity doubled, nearly equal spicules 1.8 to 2.7% of the body length, and lateral alae abruptly curved near their anterior extremity. Additional species of Raphidascaris were examined and are discussed. Hysterothylacium eurycheilum (Olsen, 1952) comb. n. (=Heterotyphlum e.) from Epinephelus itajara in Florida and the Lesser Antilles, previously known from female worms only, is redescribed as is the anterior end of Heterotyphlum himantolophi Spaul, 1927.

Diets of Baird’s Beaked Whales, Berardius bairdii, in the Southern Sea Of Okhotsk and Off the Pacific Coast Of Honshu, Japan

Stomach contents were analyzed from 127 Baird’s beaked whales, Berardizls bairdii, taken in coastal waters of Japan. During late July-August of 1985- 1987, 1989, and 1991, 107 samples were collected from off the Pacific coast of Honshu. An additional 20 samples were collected from whales taken in the southern Sea of Okhotsk during late August-September of 1988 and 1989. Prey identification using fish otoliths and cephalopod beaks revealed the whales fed primarily on deep-water gadiform fishes and cephalopods in both regions. Prey species diversity and the percentage of cephalopods and fish differed between the two regions. Off the Pacific coast of Honshu the whales fed primarily on benthopelagic fishes (81.8%) and only 18.0% on cephalopods. Eight species of fish representing two families, the codlings (Moridae) and the grenadiers (Macrouridde), collectively made up 81.3% of the total. Thirty species of cephalopods representing 14 families made up 12.7%. In the southern Sea of Okhotsk, cephalopods accounted for 87.1% of stomach contents. The families Gonatidae and Cranchiidae were the predominant cephalopod prey, accounting for 86.7% of the diet. Gadiform fish accounted for only 12.9% of the diet. Longfin codling, Laernonma longipes, was the dominant fish prey in both regions. Depth distribution of the two commonly consumed fish off the Pacific coast of Honshu indicate the whales in this region fed primarily at depths ranging from 800 to 1,200 m.

Invasive Litter, Not an Invasive Insectivore, Determines Invertebrate Communities in Hawaiian Forests

In Hawaii, invasive plants have the ability to alter litter-based food chains because they often have litter traits that differ from native species. Additionally, abundant invasive predators, especially those representing new trophic levels, can reduce prey. The relative importance of these two processes on the litter invertebrate community in Hawaii is important, because they could affect the large number of endemic and endangered invertebrates. We determined the relative importance of litter resources, represented by leaf litter of two trees, an invasive nitrogen-fixer, Falcataria moluccana, and a native tree, Metrosideros polymorpha, and predation of an invasive terrestrial frog, Eleutherodactylus coqui, on leaf litter invertebrate abundance and composition. Principle component analysis revealed that F. moluccana litter creates an invertebrate community that greatly differs from that found in M. polymorpha litter. We found that F. moluccana increased the abundance of non-native fragmenters (Amphipoda and Isopoda) by 400% and non-native predaceous ants (Hymenoptera: Formicidae) by 200%. E. coqui had less effect on the litter invertebrate community; it reduced microbivores by 40% in F. moluccana and non-native ants by 30% across litter types. E. coqui stomach contents were similar in abundance and composition in both litter treatments, despite dramatic differences in the invertebrate community. Additionally, our results suggest that invertebrate community differences between litter types did not cascade to influence E. coqui growth or survivorship. In conclusion, it appears that an invasive nitrogen-fixing tree species has a greater influence on litter invertebrate community abundance and composition than the invasive predator, E. coqui.

HEALTH RISKS TO HUMANS AND DOMESTIC LIVESTOCK POSED BY FERAL PIGS (Sus scrofa) IN NORTH QUEENSLAND

A sample of 608 adult pigs from Cape York and adjacent islands was examined for parasites and their serum tested for livestock diseases associated with the Queensland tropics. Feral pigs from North Queensland pose a significant health threat to humans with the incidence of Spargana (the plerocercoid of Spirometra erinacei) through the consumption of undercooked pork. Meliodosis (Pseudomonas pseudomalleO. Leptospirosis (L. yar. pomona). and Brucellosis (Brucella suis) are capable of infecting humans directly during unhygienic butchering of infected carcasses. In North Queensland, the widespread intermingled distribution of feral pigs and cattle increases the potential for the transmission of Actinobacillus, Leptospirosis, and Brucellosis from feral pigs to cattle. Both Europeans and Aborigines on Cape York also raise wild-caught feral pigs for meat. It is important to realize that parasites and diseases are present in young pigs and that poor husbandry practices increase the risk of infection from several parasites, i.e., Lungworm (Metastrongylus sp.) Stomach worm (Physocephalus sexalatus. Hvostrongvlus rubidus). Thorny headed worm (Macracanthorrhynchus hirudinaceus) and Kidney worm (Stephanurus dentatus). Heavy infection of these parasites reduce growth rates and cause unthriftiness in infected ani¬mals.