Sentence examples for migration tactic and from inspiring English sources

In this analysis, we estimated a separate fitness for each age-at-maturity and migration tactic and determined relative fitness for fish of the same age-at-maturity.

It appears that the present river conditions favor fish with a yearling migration tactic, and possibly a component of the phenotypic change has resulted from evolution.

We defined the proportion of juveniles destined to adopt each life-history tactic as p0 for the proportion of individuals destined to adopt the subyearling migration tactic and p1 for the proportion of individuals destined to adopt the yearling migration tactic.

That is, if evolution drives the population to a point where it has strongly committed to the yearling migration tactic and has little flexibility to respond to rapid environmental changes, the short-term consequences of restoring the river to more 'pristine' conditions could be sobering.

Once we specified p0, we could calculate adult survival rate (S y ) for each life-history type based on the proportion of adults that adopted each migration tactic (P0 and P1) and the overall adult survival rate for the entire population, ST, as follows.

The analyses are based on the Euler Lotka equation (Lotka 1959) for individuals maturing at ages 3 6: 1 where x refers to the age at maturity, r is the fitness, l x, y the survival through age x for migration tactic type y and m the corresponding fecundity (see Stearns 1992 for examples of applications of this equation to populations).

Consequently, growth opportunity was high relative to other Chinook salmon spawning areas and likely promoted a subyearling migration tactic (Connor et al. 2002; Connor and Burge 2003).

The adaptation of a yearling migration tactic represents a substantial change from historical conditions and may represent random drift, plasticity or evolutionary change, as we discuss below.

With changed riverine conditions that resulted from hydropower dam construction, some juveniles now migrate as yearlings, but more interestingly, the yearling migration tactic has made a large contribution to adult returns over the last decade.

Should efforts focus on factors that will further enhance the yearling migration tactic, which seems to have an adaptive advantage under current (and substantially altered) conditions?

The relationship between relative fitness (rREL) and the proportion of fish adopting a subyearling migration tactic (p0) is quite steep (Fig. 6).