Publications

Contents: -- Introduction -- The sampling-based approach to monitoring -- Defining objectives -- Assessing available resources -- Decision making: Matching objectives and resources -- References

A new high-precision device for measuring sediment elevation in emergent and shallow water wetland systems is described. The rod surface-elevation table (RSET) is a balanced, lightweight mechanical leveling device that attaches to both shallow ( 1 m) and deep (driven to refusal) rod bench marks. The RSET was built to complement the surface-elevation table (SET), a larger and heavier...

Populations of small-eared shrews inhabiting the northern Cordillera Oriental of Colombia and adjoining Venezuelan highlands in the vicinity of Paramo de Tama have been referred alternatively to Cryptotis thomssi or Cryptotis meridensis. Morphological and morphometrical study of this population indicates that it belongs to neither taxon, but represents a distinct, previously unrecognized...

Though the presence of a species can be unequivocally confirmed, its absence can only be inferred with a degree of probability. I used a model to calculate the minimum number of unsuccessful visits to a site that are necessary to assume that a species is absent. The model requires the probability of detection of the species per visit to be known. This probability may vary depending on...

No abstract available.

No abstract available.

No abstract available.

Eggs of nesting birds situated in peripheral areas serving as fire breaks are at risk of being sprayed with fire control chemicals. Acute toxicity tests were conducted by immersing northern bobwhite quail eggs for 10 s in different water-based concentrations of Silv-Ex® (SE), a foam-suppressant chemical, and Phos-Chek® G75-F (PC), a fire retardant chemical, on day 4 or day 11 of...

Nondetection of a species at a site does not imply that the species is absent unless the probability of detection is 1. We propose a model and likelihood-based method for estimating site occupancy rates when detection probabilities are 1. The model provides a flexible framework enabling covariate information to be included and allowing for missing observations. Via computer simulation...

Concentrations of 14 metals were studied in the soft tissues of zebra mussels (Dreissena polymorpha) and sediments from 16 Great Lakes embayments and riverine environments. Samples were collected in 1993 and 1994 during the early and late autumn period when the body mass of mussels is least affected by reproductive activities. There was a significant difference in geometric mean...

Techniques for estimation of absolute abundance of wildlife populations have received a lot of attention in recent years. The statistical research has been focused on intensive small-scale studies. Recently, however, wildlife biologists have desired to study populations of animals at very large scales for monitoring purposes. Population indices are widely used in these extensive...

Markov chain Monte Carlo (MCMC) is a statistical innovation that allows researchers to fit far more complex models to data than is feasible using conventional methods. Despite its widespread use in a variety of scientific fields, MCMC appears to be underutilized in wildlife applications. This may be due to a misconception that MCMC requires the adoption of a subjective Bayesian analysis...