Pelicans

[Deborah Drain]

Great Salt Lake Audubon has received a report of a large number of American White Pelicans in severe distress or dead in the area of the Spiral Jetty. Has anyone observed distressed and dead pelicans in the area of the spiral jetty or anywhere else in the GSL ecosystem?  It was also reported that the Pelican rookery is experiencing an almost 50% mortality rate on an annual basis due to the hyper saline waters in the north arm of the lake. 

Any information or observations that you can provide regarding distressed or dead American White Pelicans is very much appreciated,

Deb Drain 

Great Salt Lake Audubon

[John Neill]

Deb,

We will be making a trip out to Spiral Jetty over the next couple days to assess the current situation.  Any pelicans we find alive will be transported to freshwater wetlands where other pelicans are foraging or to the Wildlife Rehabilitation Center of Northern Utah.  I'll report back what we find.

I realize that seeing dead or dying pelicans, some encrusted with salt, is a troubling sight to see.  Unfortunately, this is a common, annual occurrence from late July through late September and even into early October, and it is part of the life history for juvenile pelicans from Gunnison Island colony.  During this time new fledglings depart the pelican colony and many head toward the nearest foraging area and freshwater habitat at Bear River Migratory Bird Refuge, which is a 30 mile journey.  One of their flight paths seems to travel via the Spiral Jetty, which is the closest land east of Gunnison Island.  The juveniles that are not strong enough to make it to the Refuge may stop at the Spiral Jetty.  Some are even believed to land in the water part of the way or even swim from Gunnison Island to the Jetty.  These are probably the pelicans that get encrusted with salt due to the hypersaline environment of the north of arm of Great Salt Lake.  A pelican would have to spend quite a bit of time in the water to become encrusted with salt as has been reported.  Some of the pelicans at the Jetty will regain their strength and continue on their journey, while others will perish due to lack of energy or food, dehydration, being salt encrusted, disease, or some other reason.

In 2011, we started banding juvenile pelicans on Gunnison Island and placing tags on their wings to get an idea of regional movements.  We can also use these data to assess mortality and survivability.  Since 2011, I have received 15 reports of tagged pelicans that were found dead at the Spiral Jetty and the nearby Rozel Point.  There are certainly other tagged pelicans that have not been found in the north arm of Great Salt Lake, but these 15 reports represent less than 1 percent of the total number of pelicans that were banded on Gunnison Island.

Our census data for the pelican colony on Gunnison Island over the last 10 years shows an average of over 11,000 breeding adults, which makes it the largest colony of American white pelicans in the West and in the top 5 for the continent.  Gunnison Island produces a lot of pelicans, but productivity over this same time period is only 33%, meaning only 1 out of every 3 nests produces a pelican.  So, in other words, Gunnison Island produces about 1,800 fledglings each year.  If we take our 1% number, calculated earlier from tag returns from Spiral Jetty, approximately 18 pelicans per year will die around the Jetty.  The number of pelicans affected near the Jetty will very from year-to-year, so >50 pelicans may be a bad year while less than 10 would be a good year.   In the wildlife business these are small percentages especially when you consider that about 11,000 pelican eggs (2 per nest) were laid on Gunnison Island this year.  Our wing tag data also show that roughly 40% of the pelicans that leave Gunnison Island are seen alive.  The mortality rates are rather high, but they are to be expected given the distance fledglings have to travel from the island without the support of their parents.  The trends in mortality rate and productivity of the colony have fluctuated over time, but, this year seems to fall within the normal range of variability.

Fledglings from Gunnison Island have a tough first flight off the island compared to fledglings at other pelican colonies.  Except Gunnison Island, for all the colonies I'm aware of, the fledglings can swim away from the colony and begin to forage for food.  That is not the case for Gunnison Island.  The Great Salt Lake is too salty to support fish and can lead to salt encrusted pelicans in the north arm of Great Salt Lake.  Although the north arm is supersaturated with respect to salt as a result of the rock-fill railroad causeway bisecting the lake, we consider this the "natural" condition of the lake as it may not change any time soon.  During our recent low lake elevation, the causeway is modeled to be creating a "fresher" south arm that still provides good habitat for brine shrimp and brine flies that support millions of birds.  Data from the United States Geological Survey show that the salinity of the lake as a whole, prior to and just after the completion of the causeway, was near the salinity that the north arm is today (27% salt).  The lake elevations during the building of the causeway are within 1.5 feet of the lake's elevation today.

My colleagues at the Utah Division of Wildlife Resources and I are responsible for the management of all wildlife in Utah and to serve the needs of the public.  Unfortunately, distressed wildlife is part of the natural forces of life and death.  Individual pelicans will perish, but we are more concerned about conservation efforts that benefit whole populations through efforts such as habitat improvements, disease research, and monitoring.  We do try to help pelicans and other wildlife in "artificial" distress, such as those found in the oil well seeps south of the Spiral Jetty or in mineral evaporation ponds.

The remoteness of Gunnison Island is both good and bad.  The good is that it reduces possible disturbances the breeding colony may face.  Pelicans are very sensitive to disturbance and are known to completely abandon their nests if they are disturbed, resulting in 100% mortality of the eggs and juveniles.  The bad part of the remoteness of Gunnison Island is encrusted pelicans and high mortality rates miles from a place where they can find food and drink.

If you have any further concerns, please contact me or Adam Brewerton (adambr...@utah.gov).

Thanks,

John Neill
Avian Biologist
Great Salt Lake Ecosystem Program
Utah Division of Wildlife Resources
4790 S 7500 W
Hooper, Utah 84315

801-985-3700 (Office)

wildlife.utah.gov/gsl

wildlife.utah.gov/gsl/waterbirdsurvey

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[M. H. Wallace]

Thanks for that report John.

Matthew Wallace.

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[Deborah Drain]

John,  

Thank you so much for your thoughtful and thorough response.  It is very much appreciated.  I will forward on to the individuals who were concerned about the Spiral Jetty Pelicans.  Although we understand that juvenile mortality is part of nature, it's very hard to see first hand; the individual that contacted us was concerned that the DWR was not aware of the problem.  

Like all of us, the individuals who raised concern about the state of the lake and the plight of the Pelicans, cares deeply about the GSL and was concerned that it was a more widespread issue.  

Thanks again,

Deb Drain

Great Salt Lake Audubon, Conservation Chair.

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From: John Neill <john...@utah.gov>
To: debora...@yahoo.com; UBIRD - Utah Birds and Birders <ub...@googlegroups.com>
Cc: Russell Norvell <russell...@utah.gov>; Stephanie Graham <stephani...@fws.gov>; Adam Brewerton <adambr...@utah.gov>; Mark Hadley <markh...@utah.gov>; John Luft <john...@utah.gov>
Sent: Tuesday, September 6, 2016 10:01 PM
Subject: Re: [UBIRD] Pelicans

[Joshua Taylor]

Fascinating! Thank you for that detailed report John.

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