Habitat selection and chick survival of Eurasian Golden Plovers Pluvialis apricaria altifrons during a lemming peak year in southern Lapland (Sweden)

Abstract

Abstract

Aided by radio-telemetry, this study investigates the factors involved in the survival of Eurasian Golden Plover chicks and variations in habitat selection, home ranges and diet at different times through the pre-fledging period during a lemming peak year.

Mean fledging time was 30.6 days, and 41% of all young (53% of those with known fate) survived until fledging. Starvation due to bad weather and predation were the most important chick mortality factors. Chicks hatched in isolated territories tended to have larger home range sizes than those from areas with higher densities of nests. Once hatched, young moved further away from their nest locations as they got older, hence home ranges increased with age.

Arthropod availability was studied with pitfall traps, and showed no statistical differences in abundance between habitats. Alpine heath and willow shrubs were the habitats used most by the chicks. Habitat use varied with chick age. The diet was mainly composed of insects, making up more than 80% of the total remains found in the faecal analyses. Carabidae and Bibionidae were the most common insect families found in the faeces. The later mainly due to its high abundance late in the season, whereas Carabidae and Byrrhidae seemed to be preferred prey during the whole period. Other insect families occurred in the diet at the times when they were common, indicating that the chicks opportunistically took advantage of their high abundance.

Abstract

Popular science summary

Habitat selection and chick survival of Eurasian Golden Plovers pluvialis apricaria altifrons during a lemming peak year in southern Lapland (Sweden)

Aided by radio-telemetry, this study investigates the factors involved in the survival of Eurasian Golden Plover chicks and variations in habitat selection, home ranges and diet at different times through the pre-fledging period during a lemming peak year.

Lemming numbers indirectly affect predation pressure on breeding waders. Potential predators of wader eggs and chicks will select lemmings as a preferred prey when those are numerous but will switch into wader eggs and chicks in years when few lemmings are found. Therefore, in lemming peak years, breeding success of waders will increase in tundra ecosystems.

Golden plover chicks fledged roughly after a month, about half (41-53%) of the young survived until fledging. Starvation due to bad weather (rain and cold temperatures) and predation were the most important chick mortality factors in chicks younger than 12 days old. After reaching this age, no chick was found dead, showing the importance of the first week in the life of the chicks. Raven and weasel sp. were the only two predators identified causing the deaths of the chicks.

Chicks hatched in isolated territories tended to have larger home range sizes than those from areas with higher densities of nests. Once hatched, young moved further away from their nest locations as they got older, hence home ranges increased with age and were mostly limited by the density of surrounding nests.

Arthropod availability was studied with pitfall traps. There were no differences in arthropod abundance between habitats. Despite this, alpine heath and willow shrubs were the habitats used most by the chicks, although their importance varied with chick age.

The diet was mainly composed of insects, making up more than 80% of the total remains found in the faecal analyses. Beetles (Carabidae) and Flies (Bibionidae) were the most common insect families found in the faeces. The later mainly due to its high abundance late in the season, whereas beetles seemed to be preferred prey during the whole period. Other insect families occurred in the diet at the times when they were common, indicating that the chicks opportunistically took advantage of their high abundance. Moreover, berries became an important prey especially late in the season when insects were scarce.

In this study, large inter-annual variations of snow cover during the early part of the breeding season and of rodent numbers, mainly Lemmings (Lemmus lemmus), are probably affecting survival and habitat choice of Golden Plover chicks.





Supervisor: Martin Green
Master’s degree project in Animal Ecology, 60 credits
Department of Biology, Lund University

• author: Fernández-Elipe Rodríguez, Juan
• supervisor: Martin Green
• organization: Degree Projects in Biology
• course: BIOP32 20111
• year: 2013
• type: H2 - Master's Degree (Two Years)
• subject: Biology and Life Sciences
• language: English
• id: 4057205
• date added to LUP: 2013-09-19 16:17:14
• date last changed: 2013-09-20 09:19:46