| Popis: |
The conservation history of an endemic New Zealand reptile, tuatara ( Sphenodon spp.) is used to illustrate the necessity for accurate knowledge of population abundance for the effective management and subsequent recovery of threatened species. The precision and relative cost of line transect and mark-recapture estimates of abundance were compared in a population of tuatara ( Sphenodon punctatus ) on Lady Alice Island in the Hen and Chicken Group, northern New Zealand. Estimates of density ranged 13.6–17.7 tuatara per hectare. Line transect methods provided estimates of density which were not detectably different from mark-recapture estimates. Both methods are likely to underestimate `true' tuatara abundance where only a proportion of the population is ever available for sampling. Line transects created less animal stress, less environmental disturbance, and required significantly less cost in time, effort, and personnel. The monitoring of population abundance is an integral part of the recovery process for any threatened species. Recommendations for the future monitoring of tuatara status include the further use of line transect methods as cost effective estimators of population abundance. |
Full Text from ScienceDirect