Bird Ecology and Conservation A Handbook of Techniques

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13. Exploitation Michael C. Runge, William L. Kendall, and James D. Nichols 13.1 Introduction: assessment of exploitation 13.1.1 ...

population size is an important element in the assessment of exploitation. Of course, the size of a bird population is rarely kn ...

observed growth rate is positive. (2) A trend may be due to transient dynamics. For short periods, populations that are ultimate ...

where Ntis the population size at time t, htis the harvest rate for the same time period,rmaxis the maximum growth rate, and Kis ...

Once the equilibrium population size (for a particular fixed harvest rate) is reached, the annual harvest is also constant and i ...

impact of incidental take on populations of marine mammals, species whose status and dynamics are often poorly known. The approa ...

measures are approximately known. (It is important to stress that estimates of growth rate from stable populations, where 1, a ...

production. Thus, this method guards against the other type of error: determin- ing that the exploitation is unsustainable when ...

be more protective, without long-term sacrifice of harvest, than actions that do not consider the population state. In most situ ...

and a K-selected species with a common regulatory framework. Managing only for the r-selected species might imperil the other sp ...

following hunting activities. Private hunting clubs and estates are frequently relatively small in area and are under strict con ...

Pollock et al. 1994). Another off-site approach involves contacting hunters before the hunting season and asking them to keep re ...

13.4.4Measuring harvest rate We focus attention first on estimation of legal harvest rate. In cases where it is possible to esti ...

because illegal hunters are not likely to report the kill of marked birds. Special studies using surgically implanted radio tran ...

(e.g. Williams et al. 2002). There are two basic approaches to coping with this uncertainty. Decision-theoretic approaches such ...

are 1, and thus produces growth rates that are not realizable, even in the best of conditions. To account for these additional f ...

K, the PBR formula avoids this need by substituting an estimate of density for an estimate of K. Essentially, this sets a target ...

(e.g. juvenile survival, adult survival, age at first reproduction, etc.) are affected by density. These relationships would the ...

Assessing population dynamics| 321 estimated. One way to calculate a sustainable harvest for eggs would be to insert the maximum ...