Avian influenza A virus (an orthomyxovirus) is a zoonotic pathogen with a natural reservoir entirely in birds. The influenza virus genome is an 8-segment single-stranded RNA with high potential for in situ recombination. Two segments code for the hemagglutinin (H) and neuraminidase (N) antigens used for host-cell entry. At present, 16 H and 9 N subtypes are known, for a total of 144 possible different influenza subtypes, each with potentially different host susceptibility. With >10,000 species of birds found in nearly every terrestrial and aquatic habitat, there are few places on earth where birds cannot be found. The avian immune system differs from that of humans in several important features, including asynchronous B and T lymphocyte systems and a polymorphic multigene immune complex, but little is known about the immunogenetics of pathogenic response. Postbreeding dispersal and migration and a naturally high degree of environmental vagility mean that wild birds have the potential to be vectors that transmit highly pathogenic variants great distances from the original sources of infection.

A unique window into the biological history of the Aleutian Islands is provided by the zooarchaeology of early human sites. We focus on the palaeoavifauna hunted by early Aleuts who inhabited Amchitka and Buldir islands (central Aleutians), and Shemya Island (western Aleutians) from c. 3500 yr ago to the present. Most of the seabird species recovered from these early sites varied widely in distribution and abundance through time and space. Pelagic procellariids such as short-tailed albatrosses and short-tailed shearwaters were present and abundant at most sites and at most times. During periods of increased temperatures and precipitation (e.g. 650-1100 yr BP), nearshore foragers such as cormorants and parakeet auklets increased in abundance, but during periods of cooling (e.g. 1800-2100 yr BP), piscivorous birds feeding offshore, such as murres and kittiwakes, predominated. Over three millennia, we found that marine bird populations were negatively correlated with temperature and positively correlated with precipitation. We detected hunterrelated depletions of populations breeding in accessible colonies at small scales of space and time, but we did not observe widespread or long-term effects. We conclude that local oceanography and regional changes in prey bases caused by environmental and climate change in the past had a significant impact on the distribution and abundance of Aleutian marine birds.

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Birds from the Area de Conservació n Guanacaste in northwestern Costa Rica were surveyed for blood parasites in June 2001 and December 2001-January 2002. Of 354 birds examined, representing 141 species of 35 families and 15 orders, 44 (12.4%) were infected with blood parasites. Species of Haemoproteus (4.8% prevalence), Plasmodium (0.6%), Leucocytozoon (0.3%), Trypanosoma (2.0%), and microfilariae (7.6%) were recorded. Twelve species of birds in this survey were examined for blood parasites for the first time. Several new host-parasite associations were identified.

Keyword: Canis lupus, Oncorhynchus spp., Individual specialization, Stable isotope analysis, Predator-prey interactions, Gray wolf https://mc06.manuscriptcentral.com/cjz-pubs Canadian Journal of Zoology Seasonal foraging strategies of Alaskan gray wolves (Canis lupus) in a salmon subsidized ecosystem A.E. Stanek (aestanek@alaska.edu) 1* , N. Wolf (nwolf@uaa.alaska.edu) 1 † , G.V. Hilderbrand (grant_hilderbrand@nps.gov) 2 ‡ , B. Mangipane (buck_mangipane@nps.gov) 3 , D. Abstract Despite frequent observations of wolves (Canis lupus L., 1758) using non-ungulate prey, the seasonal and inter-annual variation in the use and relative importance of alternative prey sources to gray wolf diets have not been studied at the individual scale. We used stable isotope analysis (δ 13 C and δ 15 N) of guard hair and blood components (clot and serum) collected over four years to examine the occurrence, extent, and temporal variation of salmon as a food resource by both individual wolves and social groups in Lake Clark National Park and Preserve in southwestern Alaska. Our results demonstrate substantial variability in the use of salmon over time. During summer, diets of five wolves consisted of at least 50% salmon while the diets of 17wolves consisted of primarily terrestrial prey. Over three years, one group of wolves consistently consumed salmon in summer and switched to terrestrial prey in winter. Prey choices were generally similar within social groups; however, the degree to which individuals consumed salmon was highly variable. The use of salmon as exhibited by wolves in Lake Clark is likely widespread where salmon are abundant and this finding should be taken into consideration in the conservation and management of wolves and their prey.