I got up around 6:00 this morning to cool temperatures and a little breeze after a fairly good night’s sleep. I needed a walk, so I went over to Mather Lake Regional Park, not really looking for anything in particular, just wanting the movement in Nature. It was 57º when I got there, and 63º by the time I left.

One of the first things I saw when I got into the park was a Black Phoebe singing on a fence post. Fuzzy little thing, it was fluffed up against the chill.

I also saw a female Western Bluebird, Starlings, and a male Nuttall’s Woodpecker among other birds. The Mute Swans, Mallards and some Coots were on the water, and I saw a Great Heron flying back and forth between the shores of the lake. Oh, I also saw a White-Crowned Sparrow, my first of the season!

I was hoping to see some otters or a muskrat, but no such luck. I DID see some turtles swimming in the water with the snouts up above the surface so the could catch a breath of air.

CLICK HERE for the full album of photos.

I was drawn to a cottonwood tree where there were, I knew, lots of ants tending the aphids in the petiole and leaf galls. But at this time, there were also wasps hanging around, looking for honeydew run-off. So, I looked closer, and realized that a majority of the aphids had left their galls and were congregated on the stems of the leaves. There were various instars, including some alates (winged ones), all being herded by the ants.

Among the aphids, though, were long, white, blobby looking things that were larger than the aphids but smaller than the ants. Doing a little research, I determined these were hoverfly larvae. They eat aphids, and I think I saw one of the larvae snacking on one. The ants didn’t seem to mind the larvae and, in fact, just walked over them like they weren’t there… like the zombies in “World War Z” who couldn’t see the sick people.

I also found a couple of cottonwood petiole galls that were rosy, like little apples, and they were just at the stage where the slit-door on the bottom of them was open. I cracked them open and found the early instar woolly aphids inside of them.

One still had the bloated, orange mama aphid inside (the “fundatrix”). She rolled around on the edge of the opened gall, too bloated to do much of anything else, and eventually just rolled out into my hand. Very cool… and a little funny.

I also found a webpage that had more closeups of theses aphids. Check it out. This find helped me to realize that there are TWO kinds of petiole galls on the cottonwood trees. The regular, pale green gall of the Cottonwood Petiole Gall, Poplar Petiole Gall Aphid, Pemphigus populitransversus AND the red-blushed gall of the Cottonwood Leaf-Base Gall Aphid, Pemphigus populicaulis. Learn something new every day!

I walked for about 3 hours and headed back home. This was hike #81 of my annual hike challenge.  #MigrationCelebration.

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Species List:

1. American Bugleweed, Lycopus americanus [like horehound]
2. American Coot, Fulica americana
3. Aphid, Family: Aphididae
4. Argentine Ant, Linepithema humile
5. Arroyo Willow, Salix lasiolepis
6. Black Phoebe, Sayornis nigricans
7. Broadleaf Cattail, Bullrush, Typha latifolia
8. California Quail, Callipepla californica
9. California Scrub Jay, Aphelocoma californica
10. Canada Goose, Branta canadensis
11. Common Spike-Rush, Eleocharis palustris
12. Cottonwood Leaf Gall Aphid, Pemphigus populivenae
13. Cottonwood Petiole Gall, Poplar Petiole Gall Aphid, Pemphigus populitransversus
14. Cottonwood Leaf-Base Gall Aphid, Pemphigus populicaulis [petiole, galls have a red blush, fundatrix is orange]
15. Coyote Brush, Baccharis pilularis
16. Crow, American Crow, Corvus brachyrhynchos
17. European Starling, Sturnus vulgaris
18. Fremont’s Cottonwood, Populus fremontii
19. Great Egret, Ardea alba
20. Hover Flies, Family: Syrphidae [larvae]
21. Killdeer, Charadrius vociferous
22. Mallard Duck, Anas platyrhynchos
23. Mourning Dove, Zenaida macroura
24. Mute Swan, Cygnus olor
25. Narrowleaf Willow, Salix exigua
26. Nuttall’s Woodpecker, Picoides nuttallii
27. Red-Eared Slider Turtle, Trachemys scripta elegans
28. Red-Winged Blackbird, Agelaius phoeniceus
29. River Otter, North American River Otter, Lontra canadensis [feeding site]
30. Scrub Cicada, Diceroprocta cinctifera [exuvia]
31. Soft Rush, Juncus effusus
32. Spotted Towhee, Pipilo maculatus
33. Straw-Colored Flatsedge, Cyperus strigosus
34. Tall Flatsedge, Cyperus eragrostis
35. Western Bluebird, Sialia Mexicana
36. White-Crowned Sparrow, Zonotrichia leucophrys
37. Willow Pinecone Gall midge, Rabdophaga strobiloides
38. Yellowjacket, Western Yellowjacket, Vespula pensylvanica
39. ?? Slime mold [late stage]