Population monitoring of northern fulmars (Fulmarus glacialis) and black-legged kittiwakes (Rissa tridactyla) at Skálanes Nature and Heritage Centre.
Picture of northern fulmar (Wikipedia, 2010)
This team project is managed by Clara Gyhrs and Abigail McLelland. It is approved and supervised by Dr Ruedi Nager, Lecturer in the Institute of Biodiversity, Animal Health & Comparative Medicine, School of Life Sciences, University of Glasgow.
This project aims to monitor colonies of northern fulmars and black-legged kittiwakes present on a cliff side in terms of breeding success, foraging success, and population numbers. The data collected will be compared to monitoring data from an 8-year longitudinal study by the Iceland 21 Expedition, which has a focus on colony size and general population monitoring. This long-term data has not yet been analysed by the expedition. The 2019 Iceland Expedition increased the extent of monitoring to include laid eggs, hatching, and fledging success, and we will be continuing collection of this data as well. This will then be shared with Skálanes and subsequently added to the INTERACT database, contributing to the global initiative of informative population monitoring for these species that can be used to inform future conservation and environmental management efforts. This supports one of Skálanes’ key goals of monitoring the local animals and ecosystem.
The project is important because climate change is strongly affecting the temperatures of the Northern Atlantic where sea birds such as the black-legged kittiwake (Rissa tridactyla) and the northern fulmar (Fulmarus glacialis), rear their young (Frederiksen et al., 2012). These two birds are both surface feeding pelagic species (Commission, 2009). Pelagic means these birds spend most of their life out on the open ocean away from land. The primary constituents of their diet are marine invertebrates and small fish, predominantly sand eels. Many marine ectotherms, such as the fish the seabirds feed on, have adapted to specific thermal environments. This adaptation is shaped by the low short term temperature variability in oceanic environments caused by the oceans’ high heat capacity (Frederiksen et al., 2012). The long-term global temperature increase we are experiencing has negatively affected many species of pelagic fish, which has caused a decline in piscivorous nesting seabird populations (Frederiksen et al., 2012) (Walsh et al., 1995). In addition to climate change, over-fishing in parts of their feeding and nesting range, has been evaluated to be a threat to North Atlantic populations (Commission, 2009).
Nesting cliff of northern fulmar and black-legged kittiwakes at Skálanes. Blue are fulmars and yellow are kittiwakes.
Colony sizes varies from less than ten pairs to tens of thousands, often returning to breeding sites for years. The sites of these colonies can be mixed species, as seen at Skálanes where black-legged kittiwakes and northern fulmars nest on the same cliff front.
Black-legged kittiwakes are placed on the IUCN list of vulnerable and declining species (IUCN, 2019). Breeding and general population decline of the black-legged kittiwake has been observed throughout Norwegian and UK populations (20-29%), as well as in Greenlandic population (19%) (Commission, 2009). Kittiwakes tend to lay between 1-3 eggs in April to May that hatch in June and fledge around July (Carroll et al., 2017).
Picture of black-legged kittiwake (Grube, 2019)
Northern fulmars are the most widespread and abundant seabird in the North Atlantic. They breed on coastal cliff sites, stretching from France to the Arctic islands such as Iceland, usually laying a single egg in May which usually fledges in August (Edwards et al., 2013). Northern fulmars can be used as indicator species, this means their success or decline reflects their ecosystems health and the health of other species in the ecosystem. Fulmars have previously been used as an indicator species for marine plastic abundance, and monitoring their populations numbers and breeding success throughout years can be used as an indicator of oceanic health (Piatt, Sydeman and Wiese, 2007).
The organisation Protection of the Marine Environment of the North-East Atlantic, also known as the OSPAR Commission has evaluated that more documentation is needed to quantify the overall population decline in cliff-breeding seabirds, particularly the black-legged kittiwake and the northern fulmar (Commission, 2009). It is therefore crucial to carefully monitor the populations of these sea birds at their nesting sites, as a decrease in successful rearing of chicks will lead to a global decline of these species (Croxall et al., 2012).
Due to continuing climate change, oceanic temperature increase, and current trends we expect to find a decline in average number of individuals from previous years in both species. The progress of breeding pairs is also expected to decline in line with what has been observed in other populations.
Carroll MJ, Bolton M, Owen E, Anderson GQA, Mackley EK, Dunn EK, et al. Kittiwake breeding success in the southern North Sea correlates with prior sandeel fishing mortality. Aquatic Conservation: Marine and Freshwater Ecosystems. 2017;27(6):1164-75.
Commission O. Background Document for Black-legged kittiwakes Rissa tridactyla tridactyl: Biodiversity Series Online2009 [Available from: www.ospar.org.
Croxall JP, Butchart SHM, Lascelles B, Stattersfield AJ. Seabird conservation status, threats and priority actions: a global assessment. Bird Conservation International. 2012;22:1-34
Edwards EWJ, Quinn LR, Wakefield ED, Miller PI, Thompson PM. Tracking a northern fulmar from a Scottish nesting site to the Charlie-Gibbs Fracture Zone: Evidence of linkage between coastal breeding seabirds and Mid-Atlantic Ridge feeding sites. Deep Sea Research Part II: Topical Studies in Oceanography. 2013;98:438-44.
Frederiksen M, Anker-Nielsen T, Beaugrand G, Wanless S. Climate, copepods and seabird in the boreal Northeast Atlantic – current state and future outlook. Global Change Biology. 2012;19(2).
Grube M, 2019, Immature, image, eBird.org, Lake Havasu (CA), United States, viewed 02/06/2021 <https://ebird.org/species/bklkit>
IUCN. Rissa tridactyla (Black-legged Kittiwake) Online2020 [Available from: https://www.iucnredlist.org/species/22694497/155617539.
Piatt J, Sydeman W, Wiese F. Introduction: A Modern Role for Seabirds as Indicators. Marine Ecology Progress Series. 2007;352:438-44.
Walsh DJ, Halley MP, Harris A, del Nevo IM, Sim W, Tasker ML. Seabird monitoring handbook for Britain and Ireland – A compilation of methods for survey and monitoring of breeding seabirds. Peterborough: JNCC; 1995.
2010, Creative commons, Wikipedia <https://en.wikipedia.org/wiki/Northern_fulmar#/media/File:Northern-Fulmar2_cropped.jpg>