Aims
The main aims of the monitoring of raptors in Sierra Nevada are: to ascertain the trends in their populations over time in terms of number of reproductive pairs, to record variations in the different parameters related to population dynamics, and to establish a relation between distribution and development of the populations as well as their reproductive parameters over time.
Method and effort
The monitoring focuses on identifying reproductive units. Once the number of pairs is estimated, the reproduction process is monitored. Greater effort is dedicated mainly to rupicolous species (golden eagle, Bonelli’s eagle, and peregrine falcon), although this monitoring also centres on forest species (northern goshawk, Eurasian sparrow hawk, booted eagle, short-toed snake eagle, and common buzzard).
The monitoring in the three rupicolous raptor species consists of making different visits throughout each territory, checking incubation, the number of hatched chicks, and finally the number of chicks that leave the nest. Also, the age of the reproductive pair is recorded.
Periodicity
The raptors in Sierra Nevada are monitored yearly, coinciding with the different reproduction dates.
References
Newton, I. 1979. Population ecology of raptors. T. & A.D. Poyser. Berkhamsted, UK, 399 pp.
Alkama, J., Korpimäki, E., Arroyo, B., Beja, P., Bretagnolle, V., Bro, E., Kenward, R., Mañosa, S., Redpath, S. M., Thirgood, S. y Viñuela, J. 2005. Birds of prey as limiting factors of gamebird populations in Europe: a review. Biol. Rev., 80: 171–203.
Hardey, J., Crick, H., Wernham, C. Riley, H. Etheridge, B. y Thompson, D. 2009. Raptors: A Field Guide for Surveys and Monitoring. Stationery Office (TSO). Scotland, 370 pp.