[Tweeters] Re Caspian terns ( supplemental info from my research)

[Kersti Muul]

Jill/All,

Here is some [lengthy] supplemental info regarding further questions I've
seen popping up regarding HPAI in the CATE and Seattle fragment colony
questions. 2021 was a hard year, but it was the chicks that were impacted,
adults were still 4000 strong.

In 2021 after the catastrophic heat event taking the lives of over 200 CATE
chicks (deaths directly from heat, flesh burns, broken legs and/or wings,
getting run over, etc.), there were still around 4000 adults on the roof at
T106. Previous counts have same numbers divided amongst Kimberly Clarke,
T106, and Rat Island since 2015.

Last year my drone studies counted around 1200 adults at the Coast Guard,
three weeks after the novel peregrine interaction I witnessed on June 5,
2022 (which I surmise flushed them). They laid eggs hundreds of eggs 2.5
months late; perhaps heat impacted embryonic development as was a complete
nesting failure there after laying hundreds of eggs. Or, perhaps they were
flushed. I did drone studies weekly and the numbers dwindled and eggs
disappeared.

I monitored Kimberly Clarke and Magnolia, no nesting in Everett and sloped
roof in Magnolia would not allow for nesting, just hanging out. They were
chickless and nomadic and spent a lot of time at Kellogg island. Kellogg
island is also not conducive to nesting as it is tidal and lots of
predators, including an eagle nest. 500 or so nested on Rat island with two
nesting disturbances as Steve has noted (July total nesting failure - human
interaction, and August- coyote predation resulted in only 10 successful
chicks). 2022 Seattle fragment colony seemed about 2000 less CATE than
usual.

In January 2022 their historic nesting site was demolished at T106. They
arrived in Seattle in April about a week late, in very small numbers. Only
about 100 or so at any time here. They went to coast guard, and I had
arranged to study there again, but learned roof drain work was to be done
at the same time as nesting. I approached NOAA about possibly stopping that
work if they looked they were going to nest. Unfortunately the Coast guard
informed me shortly after that they had USDA install deterrents due to the
complaints from employees. After that not much presence at all. I went out
with the Port of Seattle and went way up river to check derelict barges for
nesting, but there were none. I then checked Everett again but nothing.
Learned some nesting on Rat Island.

And then the HPAI outbreak. There were around 1500 CATE at Rat Island (most
nesting ever there) but that is yet again significantly reduced fragment
colony numbers. Im sure the T106 fragment colony makes up some of what
is/was nesting at Rat Island. This is why I say we are down 3000 or so
birds. Nobody knows where they are. Three successive years of nesting
catastrophes for the CATE.

My excerpts from *2022* timeline colab with NOAA/Port of Seattle:

7 April - Arrival time for CATE in 2022 6AM flying east towards port
vocalizing (Kersti Muul)


 5 June - Peregrine disturbances/attacks documented in T106 CATE colony.
Chasing individuals as well as flushing entire colony multiple times. Can
provide photo documentation (Kersti Muul.)

10 June- Suspicion that CATE nesting on Coast Guard building. Tern activity
high at CG Warehouse (Kersti Muul.)

1 July. To document/confirm CATE on CG Warehouse, and get counts, did first
drone survey. Survey showed ~1,130 individuals centralized on the North
side of roof. No chicks or eggs present. Many individuals bringing in fish
Can provide photo documentation. (Kersti Muul)

11 July. Accessed CG Warehouse roof to check for nesting status. Confirmed
hundreds of eggs scattered everywhere, concentrated near drains (probably
due to slope) and majority concentrated on north side of building. No
hatchlings at this point. Adults aggressively defending colony from gulls,
many individuals bringing in fish. One gull nest present on NW corner by
door. Can provide photo documentation. (Kersti Muul)

16 July. Second drone survey of CG Warehouse. ~800 individuals, (less than
July 11 but different time of day could account for this )no hatchlings.
Documented a lot of terns chasing eachother, specifically those with very
full crops; making it difficult for those individuals to return to the
colony with the fish. Individuals are a lot more spread out. Fecal matter a
lot more widespread over roof than 11 July. Can provide photo
documentation. (Kersti Muul)

16 July. Drone survey of T106. Found multiple gull chicks. No CATE present.
(Kersti Muul)

16 July. Drone survey of Kimberly Clark building in Everett to check for
nesting/occupancy of CATE. Since numbers at CG are half of 2021, thought
they might be there. Survey showed no CATE present. Can provide photo
documentation. (Kersti Muul)

26 July. Third drone survey of CG Warehouse. Only ~97 individuals present.
Most or all eggs are gone as well. Fecal matter shows utilization of much
larger area than before. Suspect nesting failure. The majority of CATE
colony has abandoned this building. Can provide photo documentation.
(Kersti Muul)


26 July. Second drone survey of T106. ~ (less than 200 individuals but need
to grid count). This number does not reflect a colony shift from CG
Warehouse. The majority of the colony is at this time MIA. Can provide
photo documentation. (Kersti Muul)

Drone survey  1 august-7 to check for hatchlings and numbers in both CG and
T106 (Kersti Muul)

3 August. Drone study of former Northwestern Industries building. High
occupancy. Not nesting (roof is slanted and it is too late anyway) Can
provide photo documentation. (Kersti Muul)

8 August. Drone study of Kellogg Island, T106, CG, Barges and Kellogg
Island. Scant presence on T106, 0 at CG, 0 on barges. High occupancy at
Kellogg Island. Can provide photo documentation. (Kersti Muul)

15 August. CATE have abandoned Northwestern Industries building. (Kersti
Muul)

15 August. CATE have abandoned Northwestern Industries building. (Kersti
Muul)

15 September. CATE have migrated, no presence here. I will arrange with
Coast Guard for fish bone collection for NOAA Fisheries diet analysis
(Kersti Muul)

5 October 6300. Collected fish bones from Coast Guard warehouse roof. Found
multiple shells of CATE eggs, predominantly in NE sector. Can provide photo
documentation.
(Muul/Good)



Kersti E. Muul
360-317-4646

Urban Conservation  & Wildlife Specialist/Biologist - Response and Rescue

Wildlife Field Biologist IV Marbled murrelet forest certified

Seattle Audubon (Birds Connect) Neighborhood Bird Project Site Leader,
Climate Watch Coordinator
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