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In 2002, world leaders committed, through the Convention on Biological Diversity, to achieve a significant reduction in the rate of biodiversity loss by 2010. We compiled 31 indicators to report on progress toward this target. Most indicators of the state of biodiversity (covering species' population trends, extinction risk, habitat extent and condition,(More)
Using data from the North American Breeding Bird Survey, we determined that most neotropical migrant bird species that breed in forests of the eastern United States and Canada have recently (1978-1987) declined in abundance after a period of stable or increasing populations. Most permanent residents and temperate-zone migrants did not show a general pattern(More)
Estimation of population change from count surveys is complicated by variation in quality of information among sample units, by the need for covariates to accommodate factors that influence detectability of animals, and by multiple geographic scales of interest. We present a hierarchical model for estimation of population change from the North American(More)
In addition to being the conduit for pathogens into hosts, tick saliva contains a broad array of secretory products that facilitate prolonged tick attachment and blood feeding. Proteins found in tick saliva modulate host hemostasis and immune responses. However, it is not clear whether ticks manipulate the immune responses of their hosts by disrupting the(More)
Ixodes scapularis ticks transmit many pathogens, including Borrelia burgdorferi, Anaplasma phagocytophilum, and Babesia microti. Vaccines directed against arthropod proteins injected into the host during tick engorgement could prevent numerous infectious diseases. Salp14, a salivary anticoagulant, poses a key target for such intervention. Salp14 is the(More)
SUMMARY Techniques for estimation of absolute abundance of wildlife populations have received a lot of attention in recent years. The statistical research has been focused on intensive small-scale studies. Recently, however, wildlife biologists have desired to study populations of animals at very large scales for monitoring purposes. Population indices are(More)
A cell culture system for the tick-borne rickettsia Anaplasma marginale offers new opportunities for research on this economically important pathogen of cattle. A. marginale multiplies in membrane-bound inclusions in host cells. Whereas erythrocytes appear to be the only site of infection in cattle, A. marginale undergoes a complex developmental cycle in(More)
Ticks are obligate ectoparasites that feed on a variety of hosts including mammals, birds and reptiles. Prolonged attachment on the host and an ability to transmit a wide variety of pathogens are the special features of tick feeding. Salivary glands are the major route for secretion of excess fluid, several proteins, and factors that counteract the host(More)
Protein secretion into the saliva from the tick salivary glands is due to exocytosis of vesicular membrane bound granular material regulated by SNARE complex proteins after salivary gland stimulation by PGE2 [Insect Biochem. Mol. Biol. 32 (2002) 1711]. Proteins associated with vesicles (v-SNAREs) are essential components of the exocytotic process.(More)
Understanding the relationship between animal community dynamics and landscape structure has become a priority for biodiversity conservation. In particular, predicting the effects of habitat destruction that confine species to networks of small patches is an important prerequisite to conservation plan development. Theoretical models that predict the(More)