Vital rate estimates for the common eiderSomateria mollissima, a data‐rich exemplar of the seaduck tribe

Abstract

This database collates vital rate estimates for the common eider (Somateria mollissima), providing a complete demographic parameterization for this slow life‐history species. Monitored across its circumpolar range, the common eider represents a data‐rich exemplar species for the less‐studied seaducks, many of which are under threat. The database contains estimates of the following vital rates: first‐year survival; second‐year survival; adult annual survival; first breeding (both age‐specific recruitment probability, and breeding propensity across potential recruitment ages); breeding propensity of established female breeders; clutch size; hatching success; and fledging success. These estimates are drawn from 134 studies, across the scientific and grey literature, including three previously inaccessible datasets on clutch size that were contributed in response to a call for data through the IUCN Species Survival Commission's Duck Specialist Group. Although clutch size has been much studied, the contributed datasets have enhanced coverage of studies reported in non‐English languages, which were otherwise only represented when cited in English‐language publications. Breeding propensity has been little studied, perhaps because adult females are often assumed to attempt breeding every year; we obtained a mean breeding propensity of 0.72. Our synthesis highlights the following gaps in data availability: juvenile and male survival; population change; and studies from Russia (at least accessible in English). The database is intended to serve population modellers and scientists involved in the policy and practice of seaduck conservation and management.

Drivers of within- and among-individual variation in risk-taking behaviour during reproduction in a long-lived bird

“…Eiders are long-lived ( ca 21 years [41]) and philopatric [42,43] birds periodically relying on intermittent breeding [44]. Females were ringed when caught breeding for the first time, which typically occurs at three years-of-age [45].…”

Conservation implications of a mismatch between data availability and demographic impact

“…In conclusion, our results highlight a propensity for disconnects between empirical demographic data and the information needs of Tony Diamond, Aevar Petersen and Grigori Tertitski, who contributed previously unavailable data (Nicol-Harper et al, 2021b). We also thank R. Spake for advice on our meta-analysis methodology.…”

“…Packages were used to handle data ( tidyr v1.1.4, Wickham, 2021) and generate figures ( metafor v2.4–0, Viechtbauer, 2010; RColorBrewer v1.1.2, Neuwirth, 2014; forestplot v1.10.1, Gordon & Lumley, 2020; fields v.13.3, Nychka et al, 2021). The underlying database is available from the Dryad Digital Repository [https://doi.org/10.5061/dryad.x3ffbg7ks] (data paper: Nicol‐Harper et al, 2021a); R code and input files for this study are deposited on Figshare (see Data availability statement ).…”

“…ANH gratefully recognises the organisers and participants of the NERC For adult survival, two studies provided multiple estimates requiring sub-meta-analysis: ID's 90 (Wood et al, 2021) and 91 (Ekroos et al, 2012). A simplified extract from the input file (based on the vital rate database in Nicol-Harper et al, 2021b) shows that they both provide multiple estimates, standard errors and sample sizes, across colonies and island cover types, respectively (Table B1). Note that selecting, for example, a single estimate per study based on maximal precision (i.e.…”

“…In order to assess whether life‐stage transitions have been studied in approximate proportion to their influence on population dynamics, we first conducted a meta‐analysis of vital rate estimates, from literature review and a call for unpublished data (Nicol‐Harper et al, 2021a). Our meta‐analytic estimates then allowed us to parameterise an MPM with weighted mean values to investigate which life‐stage transitions most influence common eider population projections.…”