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11-31 October 2002

Part 12: San Luis Reservoir

(Please note: the photos on this page were scanned from a printed Publisher document, as the original Publisher file was somehow corrupted...please excuse the lousy quality, but it's better than nothing!)

I didn't think there would be much to San Luis Reservoir, as I have fleeting memories of stopping here on the way to Contra Costa County one year, but it turns out that I had quickly birded a small part, and there was much more to explore! I started at the Basalt Area before the crack of dawn (didn't take me long to get there, even after a nice sit-down breakfast) and again was amazed at how low the lake was. This time I got my facts straight: they do indeed use these reservoirs pretty much for irrigating the San Joaquin Valley, so they regularly get pretty low this time of year. There were plenty of fishermen out, though, and what few birds were around were high in variety: several California Gulls hung out on a spit, but there was also a token Herring, and even more surprisingly an adult Western! A big flock of Common Mergansers competed for the fish, and two Great Blue Herons made chests at each other almost like grackles, their bills pointed in the air, wings down and tails up!

Great Blue Herons making chests at each other

I followed various dirt roads along the edge, and at one point I stopped short of where a bunch of fishermen had parked so I wouldn't encroach on where they had set up on the point. I got out to scan and noticed a huge fish flopping in the little finger of water next to me, and the next thing I knew I heard whoopin' and hollerin', and everybody made their way over to where I was, throwin' their lines in like crazy! I thought that was pretty funny... (There was an Eared Grebe in the middle of all that; I was hoping he wasn't gonna get snagged by accident in the frenzy!) One of the roads went to the top of one of the grassy hills (had a beautiful pair of Harriers up here), and I had a lovely view of the area, with a Rock Wren and Horned Larks to keep me company!

At the boat launch I decided to walk around the perimeter of the parking lot and bird the trees (the bulk of the habitat around the reservoir is hilly savannah, so any man-made "forests" around there are attractive to the landbirds). Got the usual kinglets, Black Phoebes, Butterbutts, etc., but the big surprise was a Barn Owl I inadvertently spooked! That got the Mockingbirds going when he landed in the pine close to them, but they soon forgot about the owl and started fighting each other...

                        

Fleeing Barn Owl and American Pipit

Next I went down to the Basalt Campground and walked around. To my utter delight, a big flock of Yellow-billed Magpies had discovered a treasure trove of some kind of pine nut, and they were constantly coming and going, literally stuffing their faces with these things and flying off to store them, I imagine. Gads, they're gorgeous! Other dickeys in the area included Hermit Thrush, Spotted Towhee, and the usual ubiquitous Butterbutts and Whiteys.

Bingeing Yellow-billed Magpies

Got a map at headquarters, then headed over to O'Neil Forebay across the highway. This was the area I had whizzed through that May, and I remember it being so-so (best bird was a lingering Ferruginous Hawk), but this time the place was packed with birds! (And the water level was sky-high, too!) The rafts were mostly coots, but lots of Ruddy Ducks were intermingled with them, and again I crawled along the shoreline, scanning every once in awhile. On the rocky shoreline close to Highway 33 were a few Least Sandpipers in with the Brewer's Blackbirds and Killdeer, and more California Gulls wheeled about the outflow there. Double-crested Cormorants liked the high tension wire structures as perches, much more so than the raptors! Beyond the rafts of coots were both Clark's and Western Grebes, several Bufflehead, and thanks to stopping at various places along the shoreline, I was able to pick out other ducks either by themselves or intermingled with the coots, including Redhead, Lesser Scaup, Ring-0necked Duck, and the real treat, a male Common Goldeneye! A flock of eight Surf Scoters was a surprise, and four scaup (two pair) at fairly close range convinced me they were Greater: the head shape of all four of them were so un-Lesser to me as to almost look "blocky", and the two females had white smudges on their cheeks. The nail of the one male I could see spread fully across the width of his bill head on, and one of the females was very obliging and spread her wing as she was preening, showing a white stripe going well into the primaries! I've had so many Greater Scaup turn into Lessers before my eyes that I tend to be overly cautious, but these guys seemed to have all the right field marks.

                    

O'Neil Forebay, packed with coots and Brewer's Blackbirds (female left, male right)

                    

Scenes around the forebay, showing surrounding oak savannah habitat

                 

Road around the area had Kestrel and Western Meadowlark

Headed across the way to San Luis Creek, scanning every flock I could. They have a couple of beaches here with more groves of Eucs, so I parked in the farthest parking lot and walked down the paved path through the heavily wooded picnic area to the beach, and then back up again. I imagine this place would be jumping in the spring (and mobbed in summer; today I had the whole place to myself), but today the Butterbutts owned the joint; one pine actually had a Hutton's Vireo come in, and a lonely Lark Sparrow sang in another, but there really wasn't much variety today. Had a group of Snowy Egrets on the beach, and another female Common Merganser, but for the most part things were really skittish here. Had Nuttall's Woodpecker and Flicker on the way back to the car, and a squealing Red-tailed Hawk on top of one of the many poles.

                

Snowy Egrets and California Gull

                

Female Common Merganser and power lines ad infinitum...

                        

Ruby-crowned Kinglet and Butterbutt

            

The waterbirds tended to hang around the sheltered coves, with varied habitat at the Meadows Area

Ran out of time after that, but I did want to make a quick swing by the Meadows Area, which was a lovely part of the forebay with marshy area along the shore (actually, several areas along the shore had marshes and willows, complete with Marsh Wrens and Song Sparrows). Added Shoveler in amongst the mob, and a scolding House Wren in the willows. The Pied-billed Grebes liked to bob close to shore, and there were a few Greater Yellowlegs as well. Had good studies of both Clark's and Western Grebes, and even one that was probably something in between!

Didn't have time to explore Dinosaur Point (that's in a different county, anyway...) so I headed back to Los Banos after that.

Continue to Panoche Wildlife Area

Go back to Merced NWR

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