A Short Walk at Gristmill, 09-06-21

I got up around 6:00 o’clock and headed over to the Gristmill Recreation Area to see if I could find galls there. It was 61º when I got there but got up to 102º by the afternoon.  PM2.5 AQI levels reached:  184 AQI (Unhealthy) .

A Black-Tailed Jackrabbit, Lepus californicus, picking its teeth.

 There are a variety of oak tree there including Interior Live Oaks, Valley Oaks, some Black Oaks and Holm Oaks. I was shocked, therefore, when I found only a handful of galls.  The Holm and Black Oaks gave me nothing, but it’s always fun to see them.

 On the live oaks I found Erineum mite galls, Pumpkin galls, some fold galls and Live Oak Bud galls… but that was only on two trees. I didn’t find anything at all on the other live oaks I looked at.

On the Valley Oaks, I was expecting to see Red Cone galls everywhere but I only found them on ONE tree, along with a single Yellow Wig Gall, some Jumping galls, a handful of Spined Turban galls, small Flat-Topped Honeydew galls, and stem galls. And, of course, there were Oak Apple galls on a lot of the trees.

CLICK HERE for the full album of photos.

I got a few photos of a Jumping Spider (Colonus hesperus) on one of the leaves, and it was eating its breakfast. I had to chase it from one side of the leaf to the other until it finally stopped to stare me down.

I could hear a few birds like Nuttall’s Woodpeckers, Killdeer, Belted Kingfishers, and Oak Titmice, but I couldn’t get photos of them.  I saw your basic Wild Turkeys, Common Mergansers, Mallards, Canada Geese, Wood Ducks, a Great Blue Heron, Mourning Doves, Black Phoebes and some Cedar Waxwings. There was also a small flock of Bushtits, but trying to get photos of any of them is always a challenge for me.  They’re small and they move so fast! 

I came across a birding ground that was following a “Warbling Vireo” in the treetops. I couldn’t see it, but it was fun to know that it was out there.

Not a lot happening, and I was only out for about 90 minutes because it was heating up fast, but I enjoyed the exercise.  #CABiodiversityDay. This was hike #76 in my annual hike challenge.

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Species List:

  1. Belted Kingfisher, Megaceryle alcyon [heard]
  2. Black Phoebe, Sayornis nigricans
  3. Black Walnut, Eastern Black Walnut, Juglans nigra
  4. Black Walnut Pouch Gall Mite, Aceria brachytarsa
  5. Black-Tailed Jackrabbit, Lepus californicus
  6. Bushtit, American Bushtit, Psaltriparus minimus
  7. California Black Oak, Quercus kelloggii
  8. California Ground Squirrel, Otospermophilus beecheyi
  9. California Scrub Jay, Aphelocoma californica
  10. Canada Goose, Branta canadensis
  11. Cedar Waxwing, Bombycilla cedrorum
  12. Common Fig, Ficus carica
  13. Common Merganser, Mergus merganser
  14. Crow, American Crow, Corvus brachyrhynchos
  15. Eastern Fox Squirrel, Sciurus niger
  16. Flat-Topped Honeydew Gall Wasp, Disholcaspis eldoradensis
  17. Gall Inducing Wooly Aphid, Stegophylla essigi [in live oaks, folds the leaf over itself; sometimes the leaf turns red/reddish]
  18. Great Blue Heron, Ardea herodias
  19. Holm Oak, Quercus ilex
  20. Interior Live Oak, Quercus wislizeni
  21. Irregular Spindle Gall Wasp, Andricus chrysolepidicola [on white oaks, Blue, Valley, etc.]
  22. Jumping Spider, Colonus hesperus
  23. Killdeer, Charadrius vociferous
  24. Live Oak Bud Gall Wasp, Callirhytis quercusagrifoliae
  25. Live Oak Erineum Mite Gall, Aceria mackiei
  26. Mallard Duck, Anas platyrhynchos
  27. Mourning Dove, Zenaida macroura
  28. Nuttall’s Woodpecker, Picoides nuttallii
  29. Oak Apple, California Gall Wasp, Andricus quercuscalifornicus
  30. Oak Titmouse, Baeolophus inornatus
  31. Pumpkin Gall Wasp, Dryocosmus minusculus
  32. Red Cone Gall Wasp, Andricus kingi
  33. Rio Grande Wild Turkey, Meleagris gallopavo intermedia
  34. Spined Turban Gall Wasp, Cynips douglasii [summer gall, pink, spikey top]
  35. Turkey Vulture, Cathartes aura
  36. Valley Oak, Quercus lobata
  37. Western Gray Squirrel, Sciurus griseus
  38. White-Breasted Nuthatch, Sitta carolinensis
  39. Wood Duck, Aix sponsa
  40. Yellow Wig Gall Wasp, Andricus fullawayi