William J. Sydeman, Ph.D., President & Farallon Institute Senior Scientist, Pacific Anomalies Science and Technology Workshop, May 6, 2015 starting at 1:34:45 (emphasis added):
- This [chart] shows the nesting success of the brown pelicans in the Gulf of California… 2010-13, of about 22,000 pairs that are nesting, an average production of about 1 young per pair. In 2014… The productivity was essentially zero. So there’s very low breeding propensity and very low productivity.
- That’s what a typical colony looked like in Apr 2006… the same image in 2014 — so nobody was home.
- And then another place… Hermann’s Gulls its another species, this is what the colony looked like in May of 2004. And 2014, again nobody was home, no efforts [see photo on right].
- In the Channel Islands there was extremely poor seabird breeding success [according to] studies of pelicans and murrelets.
- [SE Alaska] had very poor productivity.
- In Baja [CA] we had severe food shortage… breeding propensity was zero… the birds were in such bad condition that they didn’t even try.
- The unprecedented mass mortality of auklets estimates, we haven’t finished this, but probably about 100,000 birds in the N. California Current system. Upwelling appeared to be more or less normal.
Many reports have connected the die-off to weak upwelling, for example, “NOAA… states that, in addition to higher sea-surface temperatures, there have also been weaker upwellings of cold currents. Those upwellings bring nutrients up… Cassin’s auklets, especially juveniles, have been dying in large numbers… David Bradley, BC program manager of Bird Studies Canada, said Wednesday there is “definitely a spike” [but] “it’s a big mystery” as to why the birds have been dying and he is waiting to see whether US researchers can confirm a correlation.”
Sydeman et al. (pdf), May 2015: … near-zero reproductive effort and breeding success was observed for seabirds in the Gulf of California and southern California Current, and poor to average breeding success was observed for most species in the northern California Current, Gulf of Alaska, and in the western Aleutian Islands… a mass-mortality event of Cassin’s auklet… perhaps 100,000 individual birds [was] concentrated off Oregon and Washington… mechanisms [other than ocean warming] probably affected breeding… and mortality.
US Fish & Wildlife (pdf), May 14, 2015: The purpose of this letter is to share information regarding recent California brown pelican mortality events… Nearly complete colony failure occurred in 2012 [at Anacapa Island], when only five chicks are known to have fledged… No brown pelican data were collected on Anacapa Island in 2013. In 2014, very low reproductive success was observed throughout much of the California brown pelican’s breeding range… At Anacapa Island, early-season nest abandonment was very high in 2014.
Published: June 11th, 2015 at 10:36 pm ET