Geoscience Reference
In-Depth Information
effects is violated and the effect is not evaluated, then data collected from
marked animals will be biased. It follows that if significant marker effects
remain undetected or unaddressed, conservation and management actions
based on those results might not be appropriate. In addition, recent guidelines
established by institutional animal care and use committees require that mark-
ing protocols minimize pain and stress to study animals (Friend et al. 1994). If
researchers collectively ignore the development, evaluation, and application of
animal markers acceptable to such committees, and fail to publish results of
studies not finding significant effects, then some research might be needlessly
jeopardized or precluded.
The purpose of this chapter is to present examples of the effects markers
can have on animals and to examine critically the treatment of potential mark-
ing effects by ecologists. We use the word
effect
to mean unusual or abnormal
behavior, an abnormal function, or abnormal reproduction or survival. We use
significant
to indicate statistical results and
important
to indicate an observed
effect and implication for studies. We emphasize the shortcomings of various
marking techniques to animal biology. Our discussion is restricted to effects of
markers, and thus does not include a specific review of handling effects. Fur-
thermore, we do not present results specific to causes of pain or stress because
essentially no data exist from wildlife. First, we present the variety of marking
techniques that are available for, and explore possible implications of markers
on, various taxonomic groups. Next, we review recently published articles to
examine how researchers consider potential marking effects. Finally, we discuss
how potential marking effects can be minimized and evaluated in future stud-
ies. Consistent with the theme of this volume, the approach we have taken is
often critical of existing information and protocols. However, such an ap-
proach is necessary if researchers are to improve the overall quality of data
being generated from ecological studies (Peters 1991).
Review of the Literature
j
Nietfeld et al. (1994) described available marking techniques (excluding mark-
ing with radiotransmitters) and generally reviewed marking techniques for
vertebrates (excluding fish). Samuel and Fuller (1994) provided similar infor-
mation about radiotransmitters. Stonehouse (1978) edited a topic about ani-
mal marking, and other overviews dealing with selected vertebrate groups
include Stasko and Pincock (1977), Wydowsky and Emery (1983), and Parker
et al. (1990) for fish; Ferner (1979) for amphibians and reptiles; and Marion
