Pinniped Abundance and Distribution in the North Pacific Alaska and California Current Ecosystems Programs, Marine Mammal Lab, Alaska Fisheries Science Center

Home , Pinniped, San Miguel Island, Steller sea lion

28 May, 2018. Marine Mammal Commission, Seattle Status and Trends: Pinniped Abundance and Distribution in the North Pacific Alaska and California Current Ecosystems Programs, Marine Mammal Lab, Alaska Fisheries Science Center

T. Gelatt, A. Altukhov, B. Brost, V. Burkanov, K. Chumbley, J. Cutler, B. Fadely, D. Johnson, C. Kuhn, M. Lander, K. Luxa, N. Pelland, R. Ream, B. Sinclair, J. Sterling, K. Sweeney, W. Testa, R. Towell, W. Walker, T. Zeppelin R. DeLong, P. Gearin, J. Harris, S. Melin, T. Orr. P. Boveng, G. Brady, M. Cameron, C. Christman, P. Conn, S. Dahl, S. Hardy, J. Jansen, J. London, B. Mcclintock, E. Moreland, E. Richmond, I. Trunkhanova, J. Verhoef, H. Ziel. Steller sea lion abundance and stock structure

1.0 0.9 0.8 Listed > 80% ENDANGERED 0.7 decline 0.6 0.5 0.4 0.3 Relative abundance Relative 0.2 0.1 0.0 Samalga 1975 1980 1985 1990 1995 2000 2005 2010 2015 DE-LISTED Year Pass Removed Dec 2013

• Two Distinct Population Segments: wDPS endangered, eDPS delisted • Sub-structure within wDPS • Asia, “Oceanic” AK west of Samalga Pass, “Shelf” AK east of Samalga Pass • Regional variation in recent population trends 2017 Steller sea lion survey Surveyed from southeast Alaska and into the western Gulf of Alaska (through the Shumagin Islands), as well as up into the eastern Bering Sea. Western DPS trend since low point in 2002 Overall, between 2002 and 2017, the wDPS non-pups were increasing 2.14%/yr and pups 1.78%/yr. This is a lower rate of increase than what we reported in our previous tech memo analyzing data up to 2015 (Fritz et al 2016):

Non-pups Pups Realized count in 2017 was lower than anticipated because of declines in pups in E. and C. GOA

**Shown from 2002, the year of the lowest pup and non-pup abundance in the wDPS Steller sea lion (wDPS) PUPS - Decline in Gulf of Alaska from 2015-2017

Seal Rocks Wooded (Fish) Chiswell Outer (Pye) Graves Rocks Ushagat Sugarloaf White Sisters Biali Rocks Marmot Southeast Hazy Twoheaded Alaska E GULF (eDPS) Forrester Chowiet Chirikof -33% -6% C GULF -17% W GULF 1% (from 1999-2015 Increased 3.67%/y) Steller sea lion (wDPS) NON-PUPS - Decline in Gulf of Alaska from 2015-2017

Seal Rocks Wooded (Fish) Chiswell Outer (Pye) Graves Rocks Ushagat Sugarloaf White Sisters Biali Rocks Marmot Southeast E GULF Hazy Twoheaded Alaska -17% (eDPS) Forrester Chowiet Chirikof -12% C GULF 14%

W GULF Atypical movement of ~1,000 3% sea lions E GULF to C GULF (normal rate (not to SE AK or W GULF) of increase) E/C GULF combined NP counts: similar from 2015 to 2017 despite 3.37%/y growth 2000-2015 What happened? (Rapid communication within AFSC) North Pacific Warm water anomalies 2014 -2017 Marine Heat Wave of 2014-16 (“unprecedented intensity and duration”) N. Bond 5/18/18 Nov. 4, 2017: Climate change preview? Pacific Ocean ‘blob’ appears to take toll on Alaska cod Gulf of Alaska Pacific cod populations appear to have nose-dived, a collapse fishery scientists believe is linked to warm water temperatures known as “the blob” that peaked in 2015 “Higher temperatures sped up the rate at which young cod burned calories while reducing the food available for the cod to consume.”

“The blob began to take hold in 2014, and within a year had raised temperatures as much as 7 degrees F in some surface waters of the Gulf of Alaska. In deeper waters, where cod feed, the temperature rose by more than 1 degree F”. S. Barbeaux, AFSC Warm Water in the Gulf of Alaska 2014-2015 and Decreased Abundance of Pacific Cod

Gulf of Alaska Pacific Cod Biomass (tons) Bottom Trawl Survey Data 1984-2017 1,000,000

900,000 Biomass in 2017 Rec. Catch Quotas in 2018 800,000 Lowest on record 78% reduction in order 58% lower than 2015 to maintain minimum 700,000 stock size 600,000 500,000 400,000 300,000 200,000 100,000 0 1984 1987 1990 1993 1996 1999 2001 2003 2005 2007 2009 2011 2013 2015 2017 Gulf of Alaska Impacts - North Pacific Warm water anomalies 2014 -2017

Pacific cod SSL Winter Diet (millions of fish) (% FO) 46%

Between 2015 and 2017 Pacific cod declined ~70% (AFSC bottom trawl surveys) cod is 45.9% FO in SSL winter diet in Gulf of Alaska British Columbia Steller Sea Lions

• 1971-2013 – Non pups increased an average of 3.8%/ year. Pups increased 4.8% • Most Recent Survey 2013: 22,135 non-pups, 6,317 pups. • Estimated population on B.C rookeries 32,900 (31,200-33,900).

Non Pups 1971 - 2013 Pups 1971 - 2013

Olesiuk, P.F. 2018. Recent trends in Abundance of Steller Sea Lions (Eumetopias jubatus) in British Columbia. DFO Can. Sci. Advis. Sec. Res. Doc. 2018/006. v + 67 p. Steller sea lion non-pup counts in Russian Far East 2002 - 2017

Overall, the Asian stock of non-pup counts significantly decreased an average of -1.3% y-1 (-2.6%y-1 , -0.1%y-1 ) from 2002-2017. Resulting in an estimated - 21% (-38%, -1%) decrease in nonpup counts over the 15 year span

-4.1% (-5.4, -2.8) Northern fur seal abundance, stock structure, trends

• ~1,100,000 northern fur seals in North Pacific • Two stocks in US: Eastern Pacific, California; mixed during winter migration • Eastern Pacific stock designated as “depleted” under the MMPA (1988) • Regional variation in population trends

U.S. Department of Commerce | National Oceanic and Atmospheric Administration | NOAA Fisheries | Alaska Fisheries Science Center | Page 14 Northern fur seal pup production – Pribilof Islands Overall pup production declined 8.6% since 2014. SP down 12% since 2014, SG up 8.6%.

-5.9%/y < 0.01 increase

-4.0%/y

-4.4%/y

< 0.01 decrease non-sig decrease California Sea Lion Recovery, MNPL and K

1. California sea lion assessment (Laake et al 2018 J. Wildl. Mgt. DOI:10.1002/jwmg.21405) • Reconstruct population growth using 38 years of pup births and 28 years of age-specific survival rates through 2014; fit to generalized logistic model to: • Determined MNPL (183,482) and K (275,298) • Breeding range expansion to Año Nuevo and Farallon Islands; over 1,000 pups each in 2017 (M. Lowry, SWFSC) California Sea Lion UME

California sea lion population Unusual Mortality Event (UME: 2013-2017) linked to unusual oceanographic conditions • Began in 2013 with mass pup strandings • Intensified in 2014 and 2015 due to ocean heat wave (aka Blob) • Continued in 2015 and 2016 during El Niño • 2013-2015 pup cohorts experienced record low growth rates that resulted in low survival and decreased total population abundance

Recovery: 2017 pup births back to long-term average; exceptionally high growth rates to 7 months of age Steller Sea Lion Post-Delisting Eastern DPS in Oregon and Washington

• Delisted 2013 Survival • Pre-delisting survival to age of recruitment: N. California/Oregon population comparable to rest of EDPS (Wright et al. 2017 J. Mamm. 98:885-894) • Plan to Estimate survival during post-delisting period through 2019 • New rookery established on Washington coast (Carroll Island & Sea Lion Rocks – 133 pups)where none was historically known Steller pup counts in Washington, 1987-2017 140

120

100

60 Pup Pup count

0 1987 1989 1991 1993 1995 1997 1999 2001 2003 2005 2007 2009 2011 2013 2015 2017 Year California Stock Northern Fur Seals

• Breed on San Miguel and Farallon Islands, California

• SMI colony established ~ 1964 w/ tagged immigrants from Russian and US Bering sea populations

• Farallons colony established 1996 w/ tagged immigrants from San Miguel Island

Adam's Cove Castle Rock 4500 San Miguel Island 4000 Southeast Farallon Island 5000 3500 3000 4000 2500 3000 2000 1500 2000 1000 Total Production Total 1000 500 countLivepup

0 0

1996 1998 2000 2002 2004 2006 2008 2010 2012 2014 2016

2011 1999 2001 2003 2005 2007 2009 2013 2015 1997 Year Year Guadalupe Fur Seal

• Abundance estimate in 2010 is ~20,000 animals in Mexico at Guadalupe Island and San Benito Islands (Carretta et al 2017. Pac SSR). Slowly increasing & spreading. Temporary decreases influenced by El Nino events. • Small numbers of animals on San Miguel Island, California with 2-3 pups born annually • Hybridization occurring with California sea lions Northern Elephant Seal

• 3.8% / year 1988 – 2010. ~40,684 pups at 11 rookeries in 2010. • Total U.S. Population 2010: 179,000 • Total U.S. and Mexico 2010: 210,000 – 239,000

50000 U.S. Total Channel Islands 40000 Central California

30000

20000

Births (n) Births

10000

0 1950 1960 1970 1980 1990 2000 2010 2020 Year

M. Lowry, et al. 2014: Aquatic Mammals 2014, 40(1), 20-31, 22 July 6, 2017 An eruption began at Bogoslof at 16:51 AKDT July 4 (00:51 UTC, July 5) that lasted 13 minutes and was detected in seismic, infrasound, and satellite data. Winds are generally to the southeast, and initial satellite data suggest the cloud may be as high as 32,000 ft asl. AVO is raising the Aviation Color Code/Alert Level to RED/WARNING.

23 Before Dec. 2016 Oct. 9, 2017

U.S. Department of Commerce | National Oceanic and Atmospheric Administration | NOAA Fisheries | Page 24 6/1/2018 25