Líffræðifélag Íslands - biologia.is
Líffræðiráðstefnan 2019
Erindi/veggspjald / Talk/poster V4
Höfundar / Authors: Ute Stenkewitz (1), Jón Einar Jónsson (1)
Starfsvettvangur / Affiliations: University of Iceland‘s Research Center at Snæfellsnes
Kynnir / Presenter: Ute Stenkewitz
For the first time, in spring 2019, Ptarmigan Lagopus muta were surveyed on the whole of Snæfellsnes, in addition to those counts carried out in other parts of the country by the Icelandic Institute of Natural History (www.ni.is). The objective was to estimate Ptarmigan numbers for Snæfellsnes and to build a base for future monitoring.
In May, Ptarmigan males sit on prominent places in the landscape to display their territories. Males were counted using line transects, both from vehicle and on foot. The survey took eight days, but more days were spent repeating counts and adding count areas to verify initial counts and to increase sample size. Locations were Skógarströnd, Helgafellssveit, Eyrarsveit, Staðarsveit, Miklholtshreppur, Snæfellsjökull National Park and the highways Fróðárheiði, Vatnaleið, and Heydalur. The length of driven transects was > 400 km and the length of walked transects > 40 km.
Ptarmigan densities for North and West Snæfellsnes were estimated at 0.65 (CV 18.9 %) and 0.50 males/ km2 (CV 15.9 %), and for the South and highways at 0.47 (CV 55.6 %) and 0.15 males/ km2 (CV 53.2 %) (n = 73). Due to few birds seen, the coefficients of variation (CVs) for the South and Highways were too high (suggested to be < CV 25 %) to calculate reliable density estimates. Also, birds were very unevenly distributed in the South. Thus, Ptarmigan densities in the South and highways appeared lower and more variable than in the other zones. Survey methods in these areas will be adapted to obtain more reliable density estimates.