Patterns and processes of habitat-specific demographic variability in exploited marine species
Abstract
Population dynamics are governed by four demographic rates: births, deaths, immigration, and emigration. Variation in these rates and processes underlying such variation can be used to prioritize habitat conservation and restoration as well as to parameterize models that predict habitat-specific effects on population dynamics. The current understanding of patterns of habitat-specific demographic variability in exploited marine species, as well as processes underlying these patterns, was reviewed. We describe patterns of (i) habitat-specific density, followed by ontogenetic changes in habitat use, such as (ii) immigration (i.e. use as a settlement habitat) and (iii) emigration (i.e. use as a habitat for secondary dispersal to and from), and demographic rates such as (iv) growth, and (v) mortality. Despite the importance of coastal habitats for fish and invertebrate species and the vulnerability of these habitats to human impacts, there was ambiguous evidence on their role in driving of population dynamics. Roughly 63 of the studies were descriptive, 21 experimental, and 11 used a combination of descriptive and experimental approaches, whereas 5 used meta-analyses. Habitat-specific density was the most common pattern quantified, followed by growth and mortality, with relatively few examples of studies of habitat-specific larval settlement. There were many examples of the influence of coastal habitats on survival, growth, and movement, especially at young stages, and there was an emerging focus on the effects of habitat degradation on demographic rates. There needs to be an increased effort on quantifying habitat-specific demographic rates and integrating these to better predict the effects of coastal habitats on the dynamics of exploited marine populations.
Keywords
coastal area
demographic rates
fish
habitat
invertebrates
population dynamics
SOLE SOLEA-SOLEA
ESSENTIAL FISH HABITAT
PLAICE PLEURONECTES-PLATESSA
NURSERY GROUNDS
CONCENTRATION HYPOTHESIS
QUANTITATIVE DESCRIPTION
POPULATION CONNECTIVITY
RELATIVE CONTRIBUTIONS
BENTHIC INVERTEBRATES
ESTUARINE NURSERIES