3 Potential actions in response to climate change: Gannets and Cormorants (Sulidae and Phalacrocoracidae)
In this section we list and assess possible local conservation actions that could be carried out in response to identified climate change impacts on gannets and cormorants . This section is not grouped by species, but by identified impacts. If an impact or action is specific to one or a few species, this information is included in the action summary or in the footnotes.
3.1 Impact: Increased frequency/severity of storms (including wind, rain and wave action) increases foraging difficulty and/or mortality
Summary:Several local actions may be possible to limit mortality or increase recovery on a small scale, but for larger populations effective local action is difficult. Supporting the population in more general ways (increasing adult survival, limiting chick mortality) may be the most effective method.| Intervention | Evidence of effectiveness | R | S | T |
|---|---|---|---|---|
| Provide supplementary food during the breeding season | Trialled on many seabird species. Limited evidence for effectiveness in gannets and cormorants, though it has been found to have some minor benefits for non-european gannets. Typically very labour intensive and difficult, and probably only plausible for small populations. | 3 | 4 | 3 |
| Provide supplementary food during the non-breeding season | This is a hypothetical action. We found no published studies assessing this action’s effectiveness | NA | NA | NA |
| Treat sick or injured birds affected by storms | There are few reports of rehabilitating gannets, cormorants and shags. The few examples that exist note that treatment is difficult as these species are easily distressed, especially cormorants, and prone to disease in captivity. More information is needed, but generally the consensus is treatment is difficult and labour-intensive. | NA | NA | NA |
Green = Likely to be beneficial. Red = Unlikely to be beneficial, may have negative impact. Orange = contradicting or uncertain evidence. Grey = Limited evidence.
R = relevance rating. S = strength rating. T = transparency rating. All ratings on a scale of 1 to 5, where 5 is the highest.
Detail:
Provide supplementary food during the breeding season
Relevance (R): 3 studies in the evidence base focus on gannets and cormorants, 13 on other seabirds and 0 on other birds. Strength (S): The evidence base was comprised of 16 studies. Of these 10 were considered to have a good sample size, and 14 had a clear metric for effectiveness. Transparency (T): 16 studies included were published and peer-reviewed, 0 were from the grey literature, and 0 were anecdotal. Of the studies included, 13 had a published methodology, and 4 justified their rationale.