Divergence in digestive and metabolic strategies matches habitat differentiation in juvenile salmonids.

Divergent energy acquisition and processing strategies associated with using different microhabitats may allow phenotypes to specialize and coexist at small spatial scales. To understand how ecological specialization affects differentiation in energy acquisition and processing strategies, we examined relationships among digestive physiology, growth, and energetics by performing captive experiments on juveniles of wild coho salmon () and steelhead trout () that exploit adjacent habitats along natural low-to-high energy flux gradients (i.e.

Behavioural variation between piscivore and insectivore rainbow trout Oncorhynchus mykiss.

A proactive-reactive continuum integrating multiple (i.e., 3+) dimensions of animal behaviour has been reported as a major axis of behavioural differentiation, but its stability along a biological hierarchy from individuals to populations remains speculative.

Adaptive differentiation of growth, energetics and behaviour between piscivore and insectivore juvenile rainbow trout along the Pace-of-Life continuum.

Adaptive trade-offs are fundamental mechanisms underlying phenotypic diversity, but the presence of generalizable patterns in multivariate adaptation and their mapping onto environmental gradients remain unclear. To understand how life history affects multivariate trait associations, we examined relationships among growth, metabolism, anatomy and behaviour in rainbow trout juveniles from piscivore versus insectivore ecotypes along an experimental gradient of food availability. We hypothesized that (a) selection for larger size in piscivorous adults would select for higher juvenile growth at the cost of lower active metabolism; (b) elevated growth of piscivores would be supported by a greater productivity of their natal stream and more proactive foraging behaviours and (c) general patterns of multivariate trait associations would match the predictions of the Pace-Of-Life Syndrome.

The energetic consequences of habitat structure for forest stream salmonids.

Increasing habitat availability (i.e. habitat suitable for occupancy) is often assumed to elevate the abundance or production of mobile consumers; however, this relationship is often nonlinear (threshold or unimodal).

Effects of food ration on SMR: influence of food consumption on individual variation in metabolic rate in juvenile coho salmon (Onchorhynchus kisutch).

1. Consistency of differences in standard metabolic rate (SMR) between individual juvenile salmonids and the apparently limited ability of individuals to regulate their SMR has led many researchers to conclude that differences in individual SMR are fixed (i.e.

Adaptive trade-offs in juvenile salmonid metabolism associated with habitat partitioning between coho salmon and steelhead trout in coastal streams.

1. Adaptive trade-offs are fundamental to the evolution of diversity and the coexistence of similar taxa and occur when complimentary combinations of traits maximize efficiency of resource exploitation or survival at different points on environmental gradients. 2.