Effect of observer experience on the monitoring of a mouflon population

• Autorzy: Garel M. , Cugnasse J.M. , Gaillard J.M. , Loison A. , Santosa Y. , Maublanc M.L.
• Języki publikacji: EN

Abstrakty

EN

Analysis of changes in population size can be severely biased when factors related to the acquisition of data, such as differences between observer experience and changes through time in the ability of individual observers to detect animals, are not controlled for. We analysed the effect of observer qualification on the number of groups and individuals observed during two census days of a mouflonOvis gmelini musimon xOvis sp. population. The difference between professional wildlife biologists and volunteers was strong during the census day one (87 groups and 410 mouflons vs 55 and 249 by experienced observers and volunteers, respectively) but decreased significantly on the second day for the number of animals detected (390 vs 292 mouflons by experienced observers and volunteers, respectively). Our result indicates that additional training will enhance reliability of data obtained from volunteers. Given the effect of observer qualification on performance during the census, we recommend to use observers of similar and adequate qualification in population counts.

Słowa kluczowe

EN

Ovis gmelini musimon x Ovis; observer effect; monitoring abundance; volunteer; mouflon; performance; population size; monitoring change

• Wydawca: -
• Czasopismo: Acta Theriologica
• Rocznik: 2005
• Tom: 50
• Numer: 1
• Opis fizyczny: p.109-114,fig.,ref.

Twórcy

autor

Garel M.

• Universite Claude Bernard Lyon 1, 43 Boulevard du 11 novembre 1918, 69622 Villeurbanne Cedex, France

autor

Cugnasse J.M.

autor

Gaillard J.M.

autor

Loison A.

autor

Santosa Y.

autor

Maublanc M.L.

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