Gannet

Gannet

Morus bassanus
Gannet, Allan Drewitt

Introduction

With its two metre wingspan, warm yellow head, white body and black wingtips, this impressive bird will be familiar to most birdwatchers.

Even though the Gannet is restricted to a couple of dozen breeding colonies, individuals may be seen anywhere around our coast throughout the year. The breeding colonies are noisy, pungent affairs, the birds packed together with each individual just out of beak reach of its neighbours.

After the breeding season, most of our Gannets move to winter in the Bay of Biscay or further south to the coasts of west Africa, with some individuals crossing the Equator.

Gannet, Allan Drewitt

Key Stats

Status
Common
Common
Eggs
Eggs
1-1
BTO Records
BTO Records
270k records
Population and distribution stats for:

Identification

Curated resources to aid in the identification of Gannet

Songs and Calls

Listen to example recordings of the main vocalisations of Gannet, provided by xeno-canto contributors.

Call:

Movement

Information about Gannet movements and migration based on online bird portals (e.g. BirdTrack), Ringing schemes and tracking studies.

Britain & Ireland movement

View a summary of recoveries in the Online Ringing Report

Foreign locations of birds ringed or recovered in Britain & Ireland

Dots show the foreign destinations of birds ringed in Britain & Ireland, and the origins of birds ringed overseas that were subsequently recaptured, resighted or found dead in Britain & Ireland. Dot colours indicate the time of year that the species was present at the location.

  • Winter (Nov-Feb)
  • Spring (Mar-Apr)
  • Summer (May-Jul)
  • Autumn (Aug-Oct)
Foreign locations of birds ringed or recovered in Britain & Ireland

European movements

EuroBirdPortal uses birdwatcher's records, such as those logged in BirdTrack to map the flows of birds as they arrive and depart Europe. See maps for this species here.

The Eurasian-African Migration Atlas shows movements of individual birds ringed or recovered in Europe. See maps for this species here.

Biology

Lifecycle and body size information for Gannet, including statistics on nesting, eggs and lifespan based on BTO ringing and nest recording data.

Productivity and Nesting

Nesting timing

Typical (exceptional) number of broods
1

Egg measurements

Typical length x width
78x50 mm
Mass (% shell)
106g (11%)

Clutch Size

Typical number
1-1 eggs
Observed minimum and maximum
1-1 eggs

Incubation

Incubation by
Male + Female
Typical duration
46-42 days

Fledging

Type of chick
-
Typical duration
97-84 days

Survival and Longevity

Survival is shown as the proportion of birds surviving from one year to the next and is derived from bird ringing data. It can also be used to estimate how long birds typically live.

View number ringed each year in the Online Ringing Report.

lifespan

Typical life expectancy of bird reaching breeding age
17 years with breeding typically at 5 years
Maximum age from a ringed bird
37 years, 4 months, 16 days (set in 1998)

Survival of adults

All adults
0.919±0.002

Survival of juveniles

All juveniles
0.3 (to age 4)

Biometrics

Wing length and body weights are from live birds (source).

Ring Size

K

Classification, names and codes

Taxonomy, names and species codes for Gannet

Classification and Codes

  • Order: Suliformes
  • Family: Sulidae
  • Scientific name: Morus bassanus
  • Authority: Linnaeus, 1758
  • BTO 2-letter code: GX
  • BTO 5-letter code: GANNE
  • Euring code number: 710

Alternate species names

  • Catalan: mascarell atlàntic
  • Czech: terej bílý
  • Danish: Sule
  • Dutch: Jan-van-gent
  • Estonian: suula
  • Finnish: suula
  • French: Fou de Bassan
  • Gaelic: Sùlaire
  • German: Basstölpel
  • Hungarian: szula
  • Icelandic: Súla
  • Irish: Gainéad
  • Italian: Sula
  • Latvian: ziemelu sulla
  • Lithuanian: šiaurinis padukelis
  • Norwegian: Havsule
  • Polish: gluptak (zwyczajny)
  • Portuguese: alcatraz
  • Slovak: sula biela
  • Slovenian: strmoglavec
  • Spanish: Alcatraz atlántico
  • Swedish: havssula
  • Welsh: Hugan
  • English folkname(s): Solan Goose

Research

Interpretation and scientific publications about Gannet from BTO scientists.

Causes of Change and Solutions

Causes of change

There are no clear reasons for the substantial increases in Gannet numbers. Like other seabird species, fisheries discards may have played a role in the second half of the twentieth century. Gannets have high survival rates, can fly long distances to forage and are adaptable and these factors may also have helped drive increases (JNCC 2022), which have continued (at least so far) in spite of reductions in fisheries discards which are affecting other species (Bicknell et al. 2013). However, a north American study has found that increasing sea surface temperatures (due to climate change) and over-exploitation by fisheries may be affecting productivity and causing declines at the southernmost colonies in Canada (d'Entremont et al. 2022). Hence, it is possible that similar issues could affect UK colonies in the future.

Publications (9)

The status of the UK’s breeding seabirds

Author: Stanbury, A.J., Burns, F., Aebischer, N.J., Baker, H., Balmer, D., Brown, A.F., Dunn, T., Lindley, P., Murphy, M., Noble, D.G., Owens, R. & Quinn, L.

Published: 2024

Five seabird species are added to the Birds of Conservation Concern Red List in this addendum to the 2021 update, bringing the total number of Red-listed seabird species to 10, up from six since seabirds were last assessed. The Amber List of seabirds moves from 19 to 14 species, and the Green List increases from one to two species.

29.09.24

Papers

View on journal website

Seabird Population Trends and Causes of Change: 1986–2023

Author: Harris, S.J., Baker, H., Balmer, D.E., Bolton, M., Burton, N.H.K., Caulfield, E., Clarke, J.A.E., Dunn, T.E., Evans, T.J., Hereward, H.R.F., Humphreys, E.M., Money, S. and O’Hanlon, N.J.

Published: 2024

This report presents the latest seabird population trends in breeding abundance and productivity using data from the Seabird Monitoring Programme (SMP).The report documents changes in the abundance and productivity of breeding seabird species in Britain and Ireland from 1986 to 2023, and provides a detailed account of the 2021, 2022 and 2023 breeding seasons.This report includes both inland and coastal populations and trends from the Channel Islands, England, Isle of Man, Northern Ireland, Scotland, Wales and the Republic of Ireland, which are presented where sufficient data are available. The results from this report are used more broadly to assess the health of the wider environment, to inform policy and for conservation action.

21.11.24

Reports Research reports

Read the report View Online

Mismatches in scale between highly mobile marine megafauna and marine protected areas

Author: Connors, M.G., Sinnon, N.B., Agamboue, P.D., Atkinson, P.W., Bayliss, A., Benson, S.R., Block, B.A., Bograd, S.J., Bordino, B., Bowen, D., Brickle, P., Bruno, I., Carman, V.G., Champagne, C.D., Crocker, D., Costa, D.P., Dawson, T.M., Deguchi, T., Dewar, H., Doherty, P.D., Eguchi, T., Formia, A., Godley, B.J., Graham, R.T., Gredzens, C., Hart, K.M., Hawkes, L.A., Henderson, S. Henry, W., Hückstädt, L.A., Irvine, L., Kienle, S., Kuhn, C.E., Lidgard, D., Loredo, S.A., Mate, B., Metcalfe, K., Nzegoue, J., Oliwina, C.K.K., Orben, R.A., Ozaki, K., Parnell, R., Pike, E.P., Robinson, P.,. Rosenbaum, H., Sato, S., Shaffer, S.A., Shaver, D.J., Simmons, S.E., Sisson, N.B., Smith, B.J., Sounguet, G.P., Suryan, R., Thompson, D.R., Tierney, M., Tilley, D., Young, H.S., Warwick-Evans, V., Weise, M.J., Wells, R.S., Wilkinson, B.P., Witt, M.J. & Maxwell, S.M.

Published: 2022

Marine Protected Areas are designated to protect marine fauna, such as whales, sharks, turtles and seabirds, but are we getting them right? Tracking data provide valuable information on the movements and space use of species, so can these be used to help us plan and deliver better protected areas for marine magafauna and their habitats?

20.07.22

Papers

Predicting the impacts of wind farms on seabirds: An individual-based model

Author: Warwick-Evans, V., Atkinson, P.W., Walkington, I. & Green, J.A.

Published: 2017

1. Individual-based models (IBMs) are a powerful tool in predicting the consequences of environmental change on animal populations and supporting evidence-based decision making for conservation planning.2. There are increasing proposals for wind farms in UK waters and seabirds are a vulnerable group, which may be at risk from these developments.3. We developed a spatially explicit IBM to investigate the potential impacts of the installation of wind farms in the English Channel and North Sea on body mass, productivity and mortality of a breeding population of Northern gannets for which we have tracking data.4. A baseline model with no wind farms accurately represented the status of a sample of tracked gannets at the end of the 90-day chick-rearing period, and the behaviourtime budget was similar to that of tracked gannets.5. Model simulations in the presence of wind farms indicated that installations should have little impact on the gannet population, when either avoidance behaviour or collision risk scenarios were simulated. Furthermore, wind farms would need to be ten times larger or in more highly used areas in order to have population-level impacts on Alderney’s gannets.6. Synthesis and applications. Our spatially explicit individual-based models (IBM) highlight that it is vital to know the colony-specific foraging grounds of seabirds that may be impacted, when identifying potential wind farm sites, in order to account for cumulative impacts from multiple sites. Avoiding areas highly used for foraging and commuting, and avoiding large-scale developments should be effective in limiting gannet mortality as a result of collision, competition and energy expenditure. Our IBM provides a robust approach which can be adapted for other seabird populations or to predict the impacts from other types of spatial change in the marine environment.

10.08.17

Papers

The avoidance rates of collision between birds and offshore turbines

Author: Cook, A.S.C.P., Humphreys, E.M., Masden, E.A., Band, W. & Burton, N.H.K.

Published: 2014

Report of work carried out by the British Trust for Ornithology in collaboration with the Environmental Research Institute on behalf of the Marine Scotland Science.Accurately estimating birds’ risk of collision with offshore wind turbines is a key part of the decision-making process for proposed renewable developments. However, the evidence base for quantifying the number of birds likely to avoid colliding with turbines is limited. Recent BTO-led work helping to fill this gap, improving the understanding of the impacts of offshore renewables on marine wildlife.

03.12.14

Reports Research reports

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Seabird foraging ranges as a preliminary tool for identifying candidate Marine Protected Areas

Author: Thaxter, C.B., Lascelles, B., Sugar, K., Cook, A.S.C.P., Roos, S., Bolton, M., Langston, R.H.W. & Burton, N.H.K.

Published: 2012

The UK government is committed to establishing an ecologically coherent network of Marine Protected Areas (MPAs) to manage and conserve marine ecosystems. Seabirds are vital to such ecosystems, but until now these species have received little protection at sea. This is partly because there is scant information available on the oceanic regions they use at the different stages of their lifecycle. A new study led by the BTO, in partnership with the RSPB and Birdlife International, has sought to address this by bringing together work on how far UK-breeding seabirds travel from their colonies (typically in search of food for themselves or their chicks) during the breeding season.

01.01.12

Papers

View this paper online

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More evidence from Conservation Evidence.com

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