[1] The interaction of the Juan de Fuca Ridge with the Cobb hot spot has had a considerable influence on the magmatism of the Axial Segment of the ridge, the secondorder segment that overlies the hot spot. In addition to the construction of the large volcanic edifice of Axial Seamount, the Axial Segment has shallow bathymetry and a prevalence of constructional volcanic features along its 100-km length, suggesting that hot spot-derived magmas supplement and oversupply the ridge. Lavas are generally more primitive at Axial Seamount and more evolved in the Axial Segment rift zones, suggesting that fractional crystallization is enhanced with increasing distance from the hot spot because of a reduced magma supply and more rapid cooling. Although the Cobb hot spot is not an isotopically enriched plume, it produces lavas with some distinct geochemical characteristics relative to normal mid-ocean ridge basalt, such as enrichments in alkalis and highly incompatible trace elements, that can be used as tracers to identify the presence and prevalence of the hot spot influence along the ridge. These characteristics are most prominent at Axial Seamount and decline in gradients along the Axial Segment. The physical model that can best explain the geochemical observations is a scenario in which hot spot and mid-ocean ridge basalt (MORB) magmas mix to varying degrees, with the proportions controlled by the depth to the MORB source. Modeling of two-component mixing suggests that MORB is the dominant component in most Axial Segment basalts.

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We analyzed natal dispersal characteristics for 79 red wolves in the first long‐term dispersal analysis for this species. Variables analyzed included straight‐line dispersal distance, duration, timing, age, direction, and evidence of natal habitat preference induction of dispersers. We compared these values during a time when the population was increasing (1990–1998) to a period when the numbers had leveled off (1999–2007) and stabilized. We found no difference in average dispersal distance, duration or age between the two periods, and no gender bias in these characteristics. Yearlings/adults dispersed shorter distances (29.5 km) than pups (42.5 km) from 1999 to 2007 and decreased their dispersal distances during this period. After 1999, dispersals occurred 11 months of the year (compared with 7 months in 1990–1998), and the peak in pup dispersal timing shifted from December to January. The peak in dispersal timing was also significantly later for pups than yearlings/adults in 1999–2007. Dispersal direction was not random and there was a preference for a westward dispersal direction, attributed to the avoidance of water and a preference for agriculture. Natal habitat preference induction was also evident in dispersers during both time periods.