Bass Rock Research - Heat Stress

Bass Rock sits 5 kilometres north east of North Berwick. At the peak of the summer season, this steep sided volcanic rock is home to over 150,000 gannets, making it the world's largest colony of Northern gannets. Not only is it an incredible wildlife spectacle, it also provides a unique opportunity to learn more about gannets and what they can tell us about the habitats they depend on.

Understanding the marine environment is vital if we want to effectively protect and restore it. The Scottish Seabird Centre is delighted to be in partnership with some of Scotland's leading seabird scientists and the University of Glasgow to explore the question: Are Northern gannets heat stressed?

Read our Research Spotlight blogs now to find out more about the brilliant work undertaken by these researchers:

Read more about the background behind this study below.

Are Northern gannets heat stressed?
Dr Jana Jeglinski explains what this research question means and why it's important.

Our world is becoming a hotter place: The global mean temperature in 2021 was ~ 1.1°C warmer than the reference period 1850-1990 (1). Climate change, and the associated increase in air temperature, has been shown to impact many species and ecological relationships indirectly, for example through changes in the distribution of their prey.

However, the direct effects of rising ambient temperature on animal species are generally much less well understood. 'Direct effects' refer to physiological and behavioural adaptations in response to increasing temperatures. For many seabird species, climate change will likely not only have indirect but also direct effects, since many species breed on highly exposed islands and cliffs with a limited amount of shade. During the breeding season, many seabirds live in tiny, vigorously defended territories around their nest site, which does not allow any movement to seek shelter from the sun.

Gannets on Bass Rock
(C) Ruedi Nager

Seabirds are endotherms, just like us, which means that they need to maintain a stable core body temperature. Adult seabirds have a suite of behavioural mechanisms to regulate their temperature. For example, they can fly out to sea to cool down, ‘gular flutter’ (which is the seabird equivalent of sweating), or they can dissipate excess heat by directing warm blood from their core to external blood vessels in bare areas and their beak, so-called ‘thermal windows’. Crucially, young seabird chicks do not have these thermoregulatory abilities when they hatch. Research in tropical species has shown that young gannets and boobies fully depend on their parents to protect them from the sun during the first few weeks of their lives (2). Increasing ambient temperatures might therefore affect seabird chicks disproportionally, especially if they cannot be sheltered by their parents.

Seabirds are adapted to the regional climate in which they evolved. Ambient temperatures have been increasing rapidly over the past decades, in particular in Europe, with an average of 0.5 °C per decade (3). Arctic seabird species have been shown to have limited abilities to cope with excess heat since they are adapted to a much cooler climate. We know very little about the responses of temperate seabird species to rising air temperatures, but given the disproportionally high increases in Europe, we urgently need to understand this better.

Researchers Dr Jana Jeglinski, Dr Dom McCafferty, Prof Sarah Wanless and Dr Ruedi Nager have partnered with the Scottish Seabird Centre to better understand the responses of Northern gannets (Morus bassanus) to a warming climate. Gannets have exceptionally long incubation and chick-rearing periods which exposes adults and chicks to disproportionally long and increasingly challenging environmental conditions.

We will measure the microclimatic conditions around gannets’ nests with meteorological equipment, observe the behaviour of breeding gannets and their chicks, and measure their body temperature using non-invasive thermal imaging (4). Our results will allow us to better understand the vulnerability of gannets to increasing air temperatures.

(Left) The weather station collects data on temperature, humidity, solar radiation and wind speed . (Right) a thermal image of a northern gannet panting. Areas with higher surface temperatures are shown in lighter colours.
(C) Ruedi Nager, Shannon Clifford

Keep an eye on this page for upcoming research blogs and updates


(1) State of the world Climate 2021 (WMO-No. 1290)

(2) Bartholomew & Dawson (1954) Temperature regulation in young pelicans, herons and gulls. Ecology 35, 466-472

(3) The state of the climate in Europe. (2021) WMO

(4) McCafferty D (2012) Applications of thermal imaging in avian science 155, 4-15