Plant Growth and Nitrogen Metabolism of Red Grouse Lagopus lagopus scoticus in Spring

Abstract

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The utilization of heather moorland by territorial Red Grouse Lagopus lagopus scoticus

“…Indeed, grass-dominated mixtures were t h e highest ranked classes. Females may have been seeking growing shoots of cotton grasses Eriupkumm spp., which are protein-rich in spring (Moss et al 1990). During the intensive feeding periods at dawn and dusk, the preference for tall stands offering good concealment was also relaxed, and the birds made greater use of shorter vegetation, where they could achieve a higher feeding rate (Savory 1978).…”

Factors Affecting Diet Variation in the Pyrenean Rock Ptarmigan (Lagopus muta pyrenaica): Conservation Implications

“…Faecal samples were added to 10 ml acetic-formalin and recipients were shaken in an ultrasonic bath for one hour. We determined the N content of droppings (Kjeldahl method) before (total N) and after washing (free-urate faecal N), and considered the N content (% DM) of droppings after washing as a proxy of digestible protein ingested [ 36 ] and hence, of diet quality. In samples that could not be washed due to small quantities, we estimated free-urate faecal N from the following linear regression: [free-urate faecal N] = 0.518 [total faecal N]– 0.528 (r 2 = 0.705; n = 74).…”

Influence of Snowmelt Timing on the Diet Quality of Pyrenean Rock Ptarmigan (Lagopus muta pyrenaica): Implications for Reproductive Success

“…Faecal samples were added to 10 ml acetic-formalin and recipients were shaken in an ultrasonic bath for one hour to liberate droppings from the urine portion [ 50 ]. N content was estimated by the Kjeldahl method before (total N) and after washing (free-urate faecal N), and we considered N content of droppings after washing (in % DM) as a proxy of digestible protein ingested [ 51 ] and hence of diet quality. In samples that could not be washed due to small quantities, we estimated free-urate faecal N from the following linear regression: [free-urate faecal N] = 0.518 [total faecal N]– 0.528 ( r 2 = 0.705; n = 74).…”