Effects of food abundance and early clutch predation on reproductive timing in a high Arctic shorebird exposed to advancements in arthropod abundance

Abstract

SummaryClimate change may influence the phenology of organisms unequally across trophic levels and thus lead to phenological mismatches between predators and prey. In cases where prey availability peaks before reproducing predators reach maximal prey demand, any negative fitness consequences would selectively favor resynchronization by earlier starts of the reproductive activities of the predators. At a study site in northeast Greenland, over a period of 17 years, the median emergence of the invertebrate prey of Sanderling Calidris alba advanced with 1.27 days per year. Yet, over the same period Sanderling did not advance hatching date. Thus, Sanderlings increasingly hatched after their prey was maximally abundant. Surprisingly, the phenological mismatches did not affect chick growth, but the interaction of the annual width and height of the peak in food abundance did. Chicks grew especially better in years when the food peak was broad. Sanderling clutches were most likely to be depredated early in the season, which should delay reproduction. We propose that high early clutch predation may favor a later reproductive timing. Additionally, our data suggest that in most years food was still abundant after the median date of emergence, which may explain why Sanderlings did not advance breeding along with the advances in arthropod phenology.

Phenological mismatch in Arctic‐breeding shorebirds: Impact of snowmelt and unpredictable weather conditions on food availability and chick growth

“…Previous studies have also noted high, but variable levels of phenological mismatch within shorebird species breeding throughout the Arctic (Kwon et al, 2019;McKinnon et al, 2012;Reneerkens et al, 2016;Senner et al, 2017). Previous studies have also noted high, but variable levels of phenological mismatch within shorebird species breeding throughout the Arctic (Kwon et al, 2019;McKinnon et al, 2012;Reneerkens et al, 2016;Senner et al, 2017).…”

“…In fact, several studies have shown that both Subarctic-and Arctic-breeding shorebirds (Gill et al, 2014;Grabowski, Doyle, Reid, Mossop, & Talarico, 2013;Liebezeit, Gurney, Budde, Zack, & Ward, 2014;Saalfeld & Lanctot, 2017) and their invertebrate prey (Braegelman, 2016;Tulp & Schekkerman, 2008) have advanced their phenologies with recent climate change. Thus, there now appears to be several instances of phenological mismatch between the timing of shorebird hatch and peak invertebrate availability, although variability exists among species and sites (Kwon et al, 2019;McKinnon, Picotin, Bolduc, Juillet, & Bêty, 2012;Reneerkens et al, 2016;Senner, Stager, & Sandercock, 2017). Thus, there now appears to be several instances of phenological mismatch between the timing of shorebird hatch and peak invertebrate availability, although variability exists among species and sites (Kwon et al, 2019;McKinnon, Picotin, Bolduc, Juillet, & Bêty, 2012;Reneerkens et al, 2016;Senner, Stager, & Sandercock, 2017).…”

Interaction webs in arctic ecosystems: Determinants of arctic change?

“…In arctic communities, so densely linked by biotic interactions (Fig. 2), phenological shifts among interacting species may result in functional disruption (Schmidt et al 2016), although even strong trophic mismatches may remain without consequences (Reneerkens et al 2016). …”

“…Effects may be limited, as long as arthropod prey abundance exceeds a minimal threshold for sufficient chick growth for a long time after the absolute annual peak in food abundance (Durant et al 2005). Indeed, the growth of sanderling Calidris alba chicks in Zackenberg was not affected by the extent of the phenological mismatch with the date of the seasonal maximum abundance of their arthropod prey, but generally chicks grew better when the arthropod peaks were broad and high (Reneerkens et al 2016). Different arthropod groups advance at different paces in response to climate warming (Høye and Forchhammer 2008), which may also affect the quality of shorebirds’ diet (cf.…”

“…To understand how the reproductive success of birds is affected by changing arthropod resources, we still need better quantification of the proportions of the various arthropods in the diets of arctic insectivorous birds. We also need better-resolved descriptions of spatial and temporal variation in arthropod abundance in relation to the local movements of the birds and to get a better understanding of the relative importance of bottom-up (via arthropods) or top-down (via predation on bird eggs and chicks) effects on the reproductive output of birds (Reneerkens et al 2016). …”