Climate-forced seasonal mismatch between the hatching of rhinoceros auklets and the availability of anchovy

Abstract

Predator-prey relationships are key to understanding complex marine ecosystem dynamics. The match-mismatch hypothesis posits that predators time energy-intensive activities, such as reproduction, to periods of high food availability. However, predators may be constrained by various ecological or physiological processes, leading to mistimed activities relative to prey availability. We investigated inter-annual variation in the timing of breeding for a piscivorous seabird (rhinoceros auklet Cerorhinca monocerata) in relation to availability of a preferred prey item, Japanese anchovy Engraulis japonicus, using data collected over 18 yr between 1984 and 2006 at Teuri Island in the northern Japan Sea. Our primary goals were (1) to identify the climatic factors that affect the seabirds' timing of breeding, proxied by hatching date, and anchovy seasonal availability, and (2) to quantify the fitness effects of predator-prey matches and mismatches relative to climate variability. Hatching date was later in years with lower spring air temperatures. Auklets switched their feeding from sandlance and juvenile greenling to anchovy when it was transported into the birds' foraging range with the seasonal northern expansion of 13°C warm water from the south. The mismatch between hatching date and the period of high anchovy availability was most pronounced when spring air temperatures were warm, and there was a weak Tsushima (warm) Current. Spring air temperature was influenced by spring atmospheric pressure gradients in the Arctic and northern Eurasia, which drive the east Asian winter monsoon, whereas timing of the Tsushima warm water expansion was influenced by winter surface pressures over the western North Pacific. Chick growth rates, mass at fledging, and overall fledging success (fitness) were lower during mismatch years when the auklets fed less on anchovy. The auklets were constrained to adjust hatching date because the seasonal mismatch appeared to be driven by independent and unpredictable surface pressure patterns.

Environmental control of the breeding success of rhinoceros auklets at Triangle Island, British Columbia

“…The timing of this transition is almost certainly related to larger atmospheric processes over the northeast Pacific. Although different in detail, our observations are very similar to those of Takahashi et al (2001) and Watanuki et al (2009), who have shown that breeding success of rhinoceros auklets at Teuri Island in the northern Japan Sea is controlled by availability of energy-rich prey, brought to the colony by oceanic currents that vary with large scale atmospheric pressure differences over the North Pacific.…”

Forage fish abundance is a predictor of timing of breeding and hatching brood size in a coastal seabird

“…Concurrently, hatching was progressively delayed at both colonies, in contrast to many other studies documenting that earlier breeding is a common response of seabirds to a warming climate (e.g. Moe et al 2009, Reed et al 2009, Votier et al 2009, Watanuki et al 2009). Delayed breeding parallel to increasing temperatures has, however, also been demonstrated for some seabird populations in both the northern (Frederiksen et al 2004, Moe et al 2009, Shultz et al 2009) and southern hemisphere (e.g.…”

“…For seabirds, this hypothesis has been tested in a number of studies, of which many found a mismatch between predator and prey phenologies (e.g. Visser & Both 2005, Grémillet et al 2006, Watanuki et al 2009, Burthe et al 2012, but see Durant et al 2005). One general problem with the match/mismatch hypothesis, however, is that it ignores the level of food abundance, which can compensate for small mismatches in timing (cf.…”

Impacts of climate variation and potential effects of climate change on South American seabirds – a review

“…Edwards & Richardson 2004). A climate-forced seasonal mismatch between the hatching of seabird chicks and the availability of prey has been detected in zooplanktivorous and piscivorous auks (Hipfner 2008;Watanuki et al 2009). …”