SANTA MONICA BAY AUDUBON SOCIETY BLOG

Malibu pier in eastern distance past the nesting area (G. Murayama 7-23-17)

Least Terns continue nesting on Surfrider Beach next to Malibu Lagoon. The semi-monthly high tides washed out most of their nests, forcing them to re-nest. Some may have re-nested more than once. Some adults were mating a few days ago, some are sitting on eggs. Some chicks are very young while others are older, and we have juveniles stretching their wings and flying around quite competently. These birds grow up fast: 20-22 days of egg incubation, then 19-21 days from hatching to fledging.

A very young Least Tern chick (J. Waterman 7-23-17)

The Snowy Plovers are done nesting, and the winter roosting colony continues to grow. Our hatched plover chick was not banded and is now a flying juvenile.With additional juveniles arriving on Malibu Beach from northerly nesting areas, we no longer can tell for sure which one it is or even if it’s still here.

Does this Snowy Plover make you need to yawn? (J. Waterman 7-23-17)

Snowy Plover GA:OY returns for the fourth winter (J. Waterman 7-23-17)

Our old friend, Snowy Plover GA:OY, one of two birds with this color combination banded at Oceano Dunes (near central coast Pismo Beach), has returned from breeding and is again on our beach. We’ve recorded it at Malibu on 23 prior occasions spread over three winters. GA:OY has also been recorded roosting and nesting at Bolsa Chica in Orange County, but we don’t know if it’s the same bird. It’s never been recorded in both locations on the same day. Maybe we can nail down this uncertainty this winter.

High tide made a mess of our sandbag wall (L. Loeher 7-23-17)

The high tides were unkind to our sandbag wall, and the photo tells the tale. The lesson to be learned, in my opinion, is that standing or even slightly leaning sandbags simply won’t stay in place against waves rushing up the rising beach. We have to lay them down. It probably takes more sandbags to cover the same distance to the same height when they’re lying down, but it seems to be far more solid.

Least Tern on two chicks (J. Waterman 7-23-17)

We did not find the Reddish Egret as we had hoped, nor Western or Least Sandpipers or even Sanderlings, all of which have been passing through. The egret has appeared erratically over the past month.  A few birders came this morning to see it within Los Angeles County, and they were very disappointed.

Least Tern, two chicks and a big fish (J. Waterman 7-23-17)

A useful object lesson on our walks comes to us complements of the Heermann’s Gull. Most people believe that migratory birds migrate north for the summer and south for the winter. In North America, this is usually but not always true. The Heermann’s Gull regularly spend the winter on west coast beaches, including Malibu, but can be found as far north as Seattle. They breed almost entirely well to the south in the Sea of Cortez, where 95% of the species nests on the tiny island of Isla Rasa, less than 150 acres in size. Nesting is in the early spring. It’s so hot there that if they nested later, they’d cook their brains. This applies to the Elegant Terns who nest there as well.

Chocolate-colored juvenile Heermann’s Gull among post-breeding adults
(J. Waterman 7-23-17)

These gulls have had massive breeding failures for several years due to lack of prey fish. I didn’t see any juvenile birds (born in most recent spring) last year at Malibu, and probably not the year before either. When we spotted one today on the beach I made sure someone got a photo, which I sent to Kimball Garrett, Ornithology Collections Manager of the Natural History Museum of Los Angeles County, who replied:

A few juvenile Heermann’s have shown up in the past 3 weeks or so, but generally only about 1 to 5 % of the [Heermann’s] flocks, which seems like a lower percentage than back in the “good old days” when they bred very successfully in the Gulf of California most years.

Our single juvenile Heermann’s at Malibu was among 18 post-breeding adults, making it 5.3% of the entire Heermann’s flock, which fits pretty well with Garrett’s estimate.

Western Gull with starfish-snack (G. Murayama 7-23-17)

This four minute film of Isla Raza is well worth watching.

Some additional resources on Heermann’s Gull and Isla Rasa.
The Auk, 1999. Heermann’s Gull breeding biology on Isla Rasa, Enriqueta Velarde
Western Birds, 1978. Breeding Birds of Isla Raza, Jeffery Boswall & Michael Barrett
San Diego Natural History Museum Ocean Oasis – Isla Rasa
San Diego Natural History Museum – Ocean Oasis – Heermann’s Gull
10,000 Birds – Heermann’s Gull, Near Threatened
Bird Watching Daily – Warming Seas, Overfishing, drive away Elegant Terns

Greater Yellowlegs and two Black-bellied Plovers (J. Waterman 7-23-17)

Birds new for the season were: Pied-billed Grebe, Osprey, Greater Yellowlegs, Whimbrel, Marble Godwit, Ruddy Turnstone, Black Turnstone, Peregrine Falcon, Cassin’s Kingbird, Western Kingbird, Western Meadowlark.

Aaaaah – a good wing-stretch – Least Tern Juvenile (J. Waterman 7-23-17)

Many thanks to our photographers: Larry Loeher, Grace Murayama and Joyce Waterman.

Cabbage White Butterfly
(J. Waterman 7-23-17)

Our next four scheduled field trips: Possible Lower L.A. River in late August, Malibu Lagoon 8:30 & 10am, 27 August; Malibu Lagoon 8:30 & 10am, 24 September, To be announced 8:30am, Oct 14.

Our next program: To Be Announced, 3 October, 7:30 pm; Chris Reed Park, 1133 7th St., NE corner of 7th and Wilshire Blvd. in Santa Monica.

NOTE: Our 10 a.m. Parent’s & Kids Birdwalk meets at the shaded viewpoint just south of the parking area. Watch for Willie the Weasel. He’ll be watching for you and your big floppy feet.

Juvenile Least Tern has a lot of brownish plumage (J. Waterman 7-23-17)

Links: Unusual birds at Malibu Lagoon
9/23/02 Aerial photo of Malibu Lagoon

Prior checklists:
2017: Jan-June
2016: Jan-June, July-Dec 2015: Jan-May, July-Dec
2014: Jan-July, July-Dec 2013: Jan-June, July-Dec
2012: Jan-June, July -Dec 2011: Jan-June, July-Dec
2010: Jan-June, July-Dec 2009: Jan-June, July-Dec.

The 10-year comparison summaries created during the project period, despite numerous complaints, remain available on our Lagoon Project Bird Census Page. Very briefly summarized, the results unexpectedly indicate that avian species diversification and numbers improved slightly during the period Jun’12-June’14.

Black Phoebe on floating lagoon wood (L. Loeher 7-23-17)

Many thanks to Lillian Johnson, Chris Lord & Joyce Waterman for their contributions to the checklist below.
[Chuck Almdale]

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