Field studies require larger samples than do laboratory studies, because field investigators have less control over the conditions that produce variation, and many studies requiring specimens are studies of variation per se, and thus require large sample sizes. Computer modelling can help define and sometimes reduce sample size requirements. The collection of scientific specimens typically has no lasting effect on avian populations. Few ornithologists collect more than 100 individuals in a given year, and the total number of specimens collected annually for research purposes in North America is fewer than 10,000. Back to top C. Methods for Collecting Specimens Humane scientific methods of trapping and shooting are those that kill the bird instantly but avoid injury to the body parts required for the investigation.
Shooting is the most effective way to collect many species.
Ornithologists who collect birds with a shotgun should be experienced in the proper and safe use of firearms and must comply with laws and regulations governing their use. Humane use of firearms necessitates that birds be killed outright, so that the firearm and ammunition load should be appropriate for the species to be collected. Every effort should be made to avoid wounding birds, not only to minimize suffering, but also to maximize the probability of retrieving rather than losing the specimen. This technique is not appropriate for use in the laboratory, for large birds, or for diving birds. Prior administration of an anesthetic may be useful when euthanizing large birds under any conditions.