Effects of interdecadal climate variability on marine trophic interactions: rhinoceros auklets and their fish prey

Abstract

This paper presents time-series information on the diet composition and breeding performance of rhinoceros auklet Cerorhinca monocerata at Triangle Island, British Columbia, Canada, during 15 breeding seasons between 1976 and 2001. Three shifts in ocean climate occurred within British Columbia during this period (1976-77, 1989-90, 1998-99), allowing us to evaluate associations between marine environmental conditions and the reproduction of this piscivorous seabird. Lipid-rich Pacific sand lance Ammodytes hexapterus was the single most important prey delivered to chicks across years (15 yr avg. 38%; annual range 4 to 86%). Interannual variability was high, but in general breeding performance was strongest when 0+ sand lance predominated chick diets. Other annually important prey taxa included Pacific saury Cololabis saira, juvenile rockfishes Sebastes spp., Pacific herring Clupea pallasi and juvenile salmonid Oncorhynchus spp. The dietary importance of these prey also varied seasonally. Marine environmental conditions (evaluated using sea surface temperatures, SSTs) were clearly associated with reproduction of rhinoceros auklet, as both occurrence of sand lance in the diet and the growth rates of chicks diminished as spring SSTs increased (r = -0.680, p < 0.01, and r = -0.697, p < 0.01, respectively). We hypothesized that recruitment to local sand lance populations was temperature dependent. The strong negative relationship between dietary occurrence of 0+ sand lance and spring SST (r = -0.560, p < 0.05), coupled with the lack of a similar relationship for 1+ sand lance (p > 0.20), was consistent with the temperature-dependent recruitment hypothesis. Our data suggest that SSTs could interact with population age structure to affect the recruitment dynamics of Pacific sand lance. We estimated the annual dietary importance of 0+ sand lance to rhinoceros auklets using spring SST and the importance of 0+ sand lance in the diet the previous year.

Forecasting ocean warming impacts on seabird demography: a case study on the European storm petrel

“…However, the effects of extreme climatic events are far from being understood; some cases remain unexplained and results of studies are contradictory (Croxall et al 2002, Forcada & Trathan 2009, Bailey & van de Pol 2016. Breeding performance in particular may be affected directly by sea surface temperature (SST) by changing the distribution and/or abundance of important prey species (Frederiksen et al 2007), or indirectly via effects on prey recruitment (Hedd et al 2006). Furthermore, unfavourable climate conditions may induce seabirds to skip breeding (Jenouvrier et al 2005a, Olivier et al 2005, Cubaynes et al 2011 or affect nest-site conditions (Chambers et al 2011, Moreno & Møller 2011, Soldatini et al 2014).…”

Influence of Basin‐ and Local‐Scale Environmental Conditions on Nearshore Production in the Northeast Pacific Ocean

“…Cooler conditions and decreased water column stability associated with coastal upwelling indicate greater vertical mixing and nutrient availability to primary producers in the California Current (Chavez and Messié 2009;Demarcq 2009). Increases in nutrient availability cause bottom-up increases in phytoplankton and zooplankton abundances and subsequent increases in forage fish consumption (Peterson and Schwing 2003;Harris et al 2009;Boyce et al 2010;Keister et al 2011), condition (Astthorsson and Gislason 1998;Robards et al 2002;Takahashi et al 2012), and abundance (Hedd et al 2006;Thayer et al 2008;Sydeman et al 2013). Furthermore, cooler conditions can prompt favorable shifts in prey composition (Hedd et al 2006;Mackas et al 2007;Thayer et al 2008;Keister et al 2011;Gladics et al 2015).…”

“…Increases in nutrient availability cause bottom-up increases in phytoplankton and zooplankton abundances and subsequent increases in forage fish consumption (Peterson and Schwing 2003;Harris et al 2009;Boyce et al 2010;Keister et al 2011), condition (Astthorsson and Gislason 1998;Robards et al 2002;Takahashi et al 2012), and abundance (Hedd et al 2006;Thayer et al 2008;Sydeman et al 2013). Furthermore, cooler conditions can prompt favorable shifts in prey composition (Hedd et al 2006;Mackas et al 2007;Thayer et al 2008;Keister et al 2011;Gladics et al 2015). For example, during cool conditions, Pacific Sand Lances and Northern Anchovy Engraulis mordax dominate seabird diets, with commensurate increases in seabird breeding success, whereas in warm years, rockfishes and Pacific Herring are more common in seabird diets and breeding success is lower (Hedd et al 2006;Thayer et al 2008;Gladics et al 2015).…”

“…Furthermore, cooler conditions can prompt favorable shifts in prey composition (Hedd et al 2006;Mackas et al 2007;Thayer et al 2008;Keister et al 2011;Gladics et al 2015). For example, during cool conditions, Pacific Sand Lances and Northern Anchovy Engraulis mordax dominate seabird diets, with commensurate increases in seabird breeding success, whereas in warm years, rockfishes and Pacific Herring are more common in seabird diets and breeding success is lower (Hedd et al 2006;Thayer et al 2008;Gladics et al 2015). Because Black Rockfish also consume these same forage fish species (Moulton 1977;Love 2011), the increased availability of Pacific Sand Lances and Northern Anchovy may confer similar benefits to the condition and growth of Black Rockfish.…”

Timing of forage fish seasonal appearance in the Columbia River plume and link to ocean conditions

“…The abundance and timing of forage fish populations in the coastal region play a significant role in a number of ecosystem interactions, including the timing and success of seabird breeding performance (Anderson et al 1982, Safina & Burger 1988, Hedd et al 2006, Anderson et al 2007, and the ecology of sea lions (Sinclair & Zeppelin 2002, Womble et al 2005, Weise et al 2006, Womble & Sigler 2006, killer whales (Similä et al 1996), and minke whales (Macleod et al 2004). The timing of forage fish presence is also hypothesized to be an important factor in determining juvenile salmon marine survival by providing alternative prey for large piscivorous fish, marine mammals, and seabirds (Pearcy 1992).…”