Oak Grove Regional Park (near Stockton, CA)
On Tuesday, July 18, I made a relatively brief visit to Oak Grove Regional Park, which is located on the northern outskirts of the city of Stockton in San Joaquin County, CA. This 180-acre park is known for its grove of mature Valley Oaks (Quercus lobata), as well as 10-acre Oak Grove Lake. The lake was the focal point for this visit, particularly the array of insects and spiders that I found there.
Dragonflies were especially prominent, and within the hour that I was there, I spotted several Blue Dashers (Pachydiplax longipennis), a couple of Widow Skimmers (Libellula lutuosa), one or two Common Green Darners (Anax junius), several Gliders (Pantala sp.), a couple of Black Saddlebags (Tramea lacerate), and a brilliant Flame Skimmer (Libellula saturate). They were joined at times by a Western Tiger Swallowtails (Papilio rutulus), a couple of Gray Buckeyes (Junonia grisea), and more than a few Cabbage Whites (Pieris rapae). With a bit of effort, the trees around the lake (particularly the Western Sycamores [Platanus racemose] and London Plane Trees (Platanus x hispanica) yielded up their own surprises – several Zebra Jumping Spiders (Salticus scenicus), a Western Velvety Tree Ant (Liometopum occidentale), many Argentine Ants (Linepithema humile), and a strange-looking insect with a long proboscis that I think is one of the Bark Weevils (Circulonidae sp.). There were undoubtedly many species that escaped detection during my brief visit; however, the diversity of insects that I found here suggests that I should make a longer visit in the future.
Other animals at the park consisted mainly of California Ground Squirrels (Otospermophilus beecheyi), as well as a smattering of common birds – Acorn Woodpeckers (Melanerpes formicivorus), House Finches (Haemorrhous mexicanus), Black Phoebes (Sayornis nigricans), Barn Swallows (Hirundo rustica), and so on. However, I did briefly spot a Swainson’s Hawk (Buteo swainsoni) soaring overhead. This beautiful hawk is known to nest in the area, and this park seems like a great spot to find one.
