Factors contributing to declining populations

and reproductive success of seabirds on Rathlin Island

 

Puffin returning from foraging on Sandeels

Project code 

QU08-07

Contact

Dr. Neil Reid

Project staff

Lorraine Chivers

Supervisor(s)

Dr Hansjoerg Kunc & Dr Chris Harrod

Client

NIEA

Funding

NHRP

Client Officer(s)

Ian Enlander

Collaborator(s)

Dr Kendrew Colhoun, RSPB

Start date

01/10/2008

End date

30/09/2012

 

Rathlin Island supports one of the largest breeding colonies of seabirds in Ireland , with approximately 100,000 seabirds of seven different species. Rathlin qualifies as a Special Protection Area under the EU Birds Directive and is classified as an Area of Special Scientific Interest and an Important Bird Area, in part, for its seabird assemblage.

 

Rathlin Island
Rathlin Island

Evidence of substantial breeding failures among seabirds on Rathlin over a couple of breeding seasons triggered the RSPB to carry out a pilot study of productivity and provisioning behaviour in 2006. The breeding success and chick provisioning rates of a small sample of Common Guillemots Uria aalge and Black-legged Kittiwakes Rissa tridactyla were studied. Though limited by small sample sizes, the results suggested that the birds were struggling to find enough food to feed their chicks resulting in low feeding rates and poor fledging success. For example, Black-legged Kittiwake failed to breed at all while only 25-50% of Common Guillemot chicks successfully fledging.

 

This 4 year studentship, funded through the Natural Heritage Research Partnership (NHRP), will focus on foraging behaviour and breeding productivity of a number of species to understand the causes of breeding failure and recent declines. The approach will involve behavioural observations of attendance, provisioning and measures of food availability, comparison with data from elsewhere, identification of foraging range, and the assessment of links between breeding performance and trophic ecology. Specifically, we aim to:

 

1.       Determine the productivity of guillemots, razorbills and kittiwakes at Rathlin

2.       Examine the provisioning rates of guillemots, razorbills and kittiwakes at Rathlin

3.       Identify the diet of guillemots and razorbills at Rathlin

4.       Identify foraging ranges and key feeding areas

5.       Determine prey availability at key feeding areas

6.       Relate foraging and breeding parameters to food availability and quality

7.       Compare the productivity and provisioning behaviour of seabirds at Rathlin with colonies elsewhere

 

The Natural Heritage Research Partnership (NHRP) is funded by the Northern Ireland Environment Agency (NIEA)