Linking habitat selection, emigration and population dynamics of freshwater fishes: a synthesis of ideas and approaches

Abstract

– The consequences of individual behaviour to dynamics of populations has been a critical question in fish ecology, but linking the two has proven difficult. A modification of Sale's habitat selection model provides a conceptual linkage for relating resource availability and individual habitat selection to exploratory behaviour, emigration and population‐level responses. Whole‐population experiments with pupfish Cyprinodon macularius that linked all factors along this resource to population continuum lend support to this conceptual model, and illustrate that emigration may be much more common in fish populations than considered in most individual‐ or population‐based models. Accommodating emigration can enhance the ecological appropriateness of behavioural experiments and increase confidence in extrapolation of experimental observations to population‐level effects. New experimental designs and advancing technologies offer avenues for assessing population consequences of habitat selection and emigration by individual fish. Emigration often is the key linkage between individual behaviour and population responses, and greater understanding of the underlying factors affecting this often‐overlooked demographic parameter could offer new approaches for management and conservation of fishes.

Influence of flood frequency, temperature and population density on migration of Fundulus heteroclitus in semi-isolated marsh pond habitats

“…Characteristics that determine population-level change include recruitment, mortality, emigration and immigration. Despite their contribution to population processes, immigration and emigration data are frequently unavailable or their impacts perceived to be minimal; thus their importance in population dynamics is often unknown (McMahon & Matter 2006).…”

“…In contrast, ponds that are subjected to more regular tidal flooding may be cooler and higher in oxygen concentration, as well as have increased productivity which provides more food resources for fish (Froneman 2002, Balcombe et al 2005, 2007. Diminished exploration behaviour by individuals experiencing more suitable habitat conditions linked to tidal flooding may result in lower emigration rates (McMahon & Matter 2006).…”

Evaluating the effectiveness of restoring longitudinal connectivity for stream fish communities: towards a more holistic approach

“…Obstacles may also be strongly detrimental to species migrating or dispersing entirely in freshwater (Lucas and Batley 1996;Porto et al 1999;Branco et al 2012;Gough et al 2012;Benitez et al 2015). Dispersal is crucial for population persistence and is intrinsic to ecological, behavioural and evolutionary processes (McMahon and Matter 2006;Urban et al 2009). Longitudinal reconnection is increasingly a major goal of river restoration (Fullerton et al 2010;Kemp and O'Hanley 2010).…”

Coarse-scale movement patterns of a small-bodied fish inhabiting a desert stream

“…Specifically, because limited resource availability often promotes emigration (McMahon and Tash 1988;McMahon and Matter 2006), we hypothesized that the upstream perennial regions are a source habitat that supplies individuals to downstream ephemeral sink habitats. Additionally, we hypothesized that movement rates will decrease throughout the course of the study, as pupfish establish breeding territories.…”