Thursday, December 29, 2011

Birding in Sulphur Springs Valley

A winter trip to Sulphur Springs Valley has become a tradition that even Randy and the dogs look forward to. We cruise through the SE Arizona grasslands, pass Tombstone and then head for Whitewater Draw, where thousands of Sandhill Cranes rest and feed in the harvested fields. This year we had heard that there would be fewer cranes than in other years because of a lack of water in Willcox Playa, the main draw for the cranes.  But on Christmas Day there was a gray band of thousands of birds on the ground at Whitewater and endless chains of incoming new arrivals appeared constantly in the northern sky.

While I went exploring, Randy just wanted to sit and listen to the raucous calls of the cranes and mysterious rustlings in the reeds. When I came back with pictures of hunting Northern Harriers, frustrating sparrows, law-abiding shrikes, fighting coots and singing Marsh Wrens he had been watching (without binoculars) a 'big guy that was foraging in the cat tails for 'hours' ' and two little black guys stirring up the mud.

I was happy to find two little Sora Rails and started shooting away, but Randy kept pointing at the bank right in front of him to make me look at the 'big guy' - it took several attempts at triangulation to make me recognize the still shape of a stocky, extremely well camouflaged heron: an American Bittern.

He was only about 12 feet from us in an upright, frozen pose that makes him really look just like part of the bleached dry cat tails. I kept loosing him when I changed cameras, even after I knew his location.

Finally he began walking around, searching and catching food. Even though he resembles Night Herons and Green Herons, his behavior sets the Bittern apart. He nearly never exposes himself by climbing up the bank or into the branches of trees like they would - he rather stays hidden in full view among the reeds on the ground.

I had an equally close encounter with a Least Bittern while I lived in Gainesville, Florida (still searching for the slides to add the image here) and I once saw an American Bittern at Sweetwater in Tucson from a distance. Otherwise, their booming deep calls were all I could remember from Northern Germany.

Beautiful views of a Yellowlegs were nearly anticlimactic after this. But the winter guest from the tundras of northern Canada knew how to put himself into the right light in the smoothly reflecting water.

 I think it's a Greater rather than a Lesser because of the long beak.

After giving the dogs a good run in the grassland (and waiting for the two 'pups' to return from an extended visit to a not so nearby farm) we headed back towards Tucson. Going north towards Interstate 10 we enjoyed the low light on the sculpted Mustang Mountains and views of  gleaming snowfields on Chiricahuas, Huachucas and Pinalenos.

More avian excitement awaited us among the artesian ponds and swampy meadows of Benson: The meadows were literally black with birds from a distance, but swarms flying up and billowing over the road, turning in unison against the light showed their yellow heads for a moment, before swinging into the other direction and turning into a black cloud again.

Yellow-headed Blackbirds - many thousands of them. The pictures were taken as the sun just sank below the horizon, changing the color palette abruptly from warm golds to hues of icy blue.

Sunday, December 25, 2011

White Christmas in Tucson?

Not really in Tucson, but on our local Mount Lemmon. It's more than an hour's drive from our house because we have go across town before driving up Mt Lemmon Highway, the road that climbs in wide, sweeping curves from the desert at 2500 feet to nearly 10000 feet at the ski runs.

The ski slopes are already open because we had one of the wettest Decembers since precipitation has been recorded, resulting in several feet of snow at the top. The crowds stayed close to the parking lots, so we had the Marshall Gulch trail nearly to ourselves.

 Cascades of icicles, dark conifers, steep rock walls and a gurgling creek all from a winter wonderland - and our dogs enjoying the deep, fluffy snow -

 Staying mainly on the trampled path where the white stuff wasn't quite as deep and fluffy...our dogs aren't stupid!

Sunday, December 18, 2011

Of Migrants, Aliens and Mutants

A disclaimer first:  Being part of at least two of the above categories, at the Gilbert Water Ranch, in the heart of Sheriff Arpaio' s Maricopa County territory, I made sure to carry my green-card while bird watching.

 In Gilbert, 110 acres with seven large shallow basins that are used to recharge the water table with processed waste water. The eighth pond is stocked for fishing. Waste water there, too? For most visitors, wintering migratory waterbirds are the main attraction of this urban wetland.

From Bob Beatson I finally learned field-marks to differentiate between Ringnecked Ducks (rings around the beak and a white shoulder spur) that were in the majority and Lesser Scoups (above, right). The female on the left was one of several with an unusual amount of white around the beak...leucistic? Nothing special  - as Bob remarked, if it were a displaced Scooter, there would be birders lined up all along the shore....

Elegant Northern Pintails were drifting among hundreds of Long-billed Dowitchers and a few Yellow Legs. Surprise: the total absence of Northern Shovelers. They must ALL be at Sweetwater in Tucson.  American Avocets (above right with Black-necked Stilt) were still in their pale Winter plumage without any salmon blush of neck and head.
We saw an impressive phalanx half of Canada and half of Snow Geese overhead. No camera was ready.

A Snowy Egret danced and fluttered, fishing busily next to a pair of Pied-billed Grebes. Quite in contrast a Green Heron moved in on the same great fishing spot in absolute slow motion. Fishing must have been good: A Kingfisher rested satisfied and a male Osprey carried a huge fish around a female who very slowly followed him.

We watched a dispute between a Sharp-shinned Hawk and a female Kestrel. For a while he kept harassing her on her tamarisk perch. She flew up and hovered, trying to ignore him and hunt. He mobbed her in the air, then treed in a mesquite. A little later she landed there as well, then the whole tree rustled when she went after him and attacked. Finally, the Sharp-shin cleared out. Interesting: two raptors that probably go after similar prey fighting over territory?

Bob's species list was growing. Red-shouldered Blackbirds, Great Grackles, Curved-billed Trashers, Mockingbirds, Verdins, Lesser Goldfinches, Yellow Rumps, Say's Phoebes and Anna's Hummers were common, Black-tailed Gnatcatchers, and Ruby-crowned Kinglets appeared sporadically. Abert's Towhees, White-crowned Sparrows and House-finches made Bob's list, but House Sparrows and Starlings were purposefully ignored as alien invaders from Europe.

So what about those Peach-faced Lovebirds (Agapornis roseicollis, Psittacidae)? Would Bob count those? An established colony of those cute little 'mini-parrots' lives at the preserve. They are the feral descendants of escaped pets that feel very much at home in Gilbert because they are native to southwest Africa, (Namib Desert and southwest Angola) where they inhabit dry areas with shrubs or trees, usually near bodies of water.
 We found several pairs in a big umbrella shaped Chilean Mesquite, preening each other and cuddling. They are just too charming to ignore, even if they are as much an invasive species as the European Starlings. We ended up spending more time watching them then some of the natives.

And, at the end, another water Ranch specialty of the year, a leucistic Say's Phoebe. This one isn't all light colored but pied in a way that looks nearly like a regular pattern. I am glad that another birder had told us about it or I would have searched the field guide for some interesting immigrant from Mexico.

I am aware of several cases of leucism  in flycatchers from waste water recharge areas. I hope that this isn't the result of an accumulation of harmful, mutation generating substances in these birds that probably feed on insects with aquatic larvae. Most leucistic birds seem healthy enough to produce and raise offspring, which in most cases turns out phenotypically normal.

Wednesday, December 14, 2011

More bug life from the Santa Cruz River in December

Chrysomela sonorae
Even December, fresh green leaves of the willows along the Santa Cruz river support several species of leaf beetles. Here is a single freshly eclosed Chrysomela sonorae. I have found this species only once before in the Patagonia Creek Preserve, in late October.

Last instar larvae, fresh pupa with split larval skin (black), fully pigmented pupa and adult beetle all of
Plagiodera arizonae
Plagiodera arizonae can be found in great numbers on Willows all over Arizona, and I have seen all stages of development, as shown above, in early April, in August, and in December. So it seems to reproduce  year round in several generations. If you look closely at the third picture, you can see that only one layer of the leaf was eaten not all the material between the leaf-veins as a skeletonizing leaf beetle (Subfamily Galerucinae) would do. Plagiodera belongs to the subfamily Chrysomelinae.

Lexiphanes guerni (left and middle) and L. mexicanus
In the same habitat, groups of many tiny Lexiphanes guerni are hiding in the young tips of Seep Willows Baccharis salicifolia. At least on other species of this genus can be found along the river closer to the Mexican border.

Leptinotarsa lineolata adult and larva (left) and Apleurus saginatus
Burrowbrush Hymenoclea monogyra accompanies the sandy banks of the river all the way from Marana in Pima County to the Mexican Border and beyond. It feeds adults and larvae of another specialized leaf beetle Leptinotarsa lineolata. This late in the season, however, there were only a few big weevils of the species Apleurus saginatus. The adult weevils can be found mating on this plant from Semtember to December.

Brochymena sp. (Rough Stinkbug),   Neoscona oaxacensis (Western Spotted Orbweaver)
Tetragnatha sp. (Longjawed Orbweaver), 
Metaphidippus chera (Jumping Spider)
On another willow, a stinkbug and a heard of aphids were utilizing the juices of the plant while a whole army of predators was waiting its chance to sneak up on the vegetarians. There were spiders of several different families (above)

and of course ladybugs, here represented by larvae and adults of Ashy-gray Ladybugs (left) and our most common black-with-red-spots Chilocorus cacti.

Tuesday, December 13, 2011

Grasshoppers, Crickets and Katydids in December in Arizona

Dry grassland and yellowing cottonwoods, but still some green along the creek
Before it gets really cold in the desert, which can happen any time between late October and late March or not at all, insect live seems to be limited by drying-up food supplies rather than just shortened day time hours or cold nights. When for example the grasses of the Empire State Ranch (above) turned brittle and dry the enormous grasshopper population there crashed within a couple of weeks. 

Santa Cruz River in Marana on Jan. 4, 2012
 Along creeks and rivers, where a narrow belt of vegetation is still green, and even around cattle ponds where algae and water plants become accessible by the falling water level, many insects, among them many grasshoppers and crickets, are still holding out even after some freezing night time temps.

Singing male and mated pair of Tree Crickets Oecanthus sp.
Along the Santa Cruz River in Marana a continuous choir of tree crickets greets the visitor in the late afternoon. Most males are perched on big cockle-bur leaves that seem to provide especially good acoustics. Several appreciative females can be found close to every singer. The pair above right has already mated, there is a spermatophore visible at the base of her ovipositor (a little pink sphere).

Ovipositing Microcentrum rhombifolium (Greater Angle-wing Katydid)
Close to the river are large stands of willows (Salix gooddingii). At dusk a much fainter crescendo of little clicks made me search the canopy for another long-horned hopper, but it took two additional visits to finally find an extremely well camouflaged over 6 cm long female Greater Angle-wing Katydid whose male was probably the caller. This female was using her ovipositor to glue a row of her big disk-shaped eggs to a willow twig.

 Scudderia sp. (Scudder's Bush Katydids)
The purpose of the saw-like edge of the ovipositor isn't quite obvious in the Angle-wings, but there are other Katydids like the Scudderia species, that actually use this structure to separate the layers of a leaf to push the egg disks between them. Thanks to Carl Olson who made these images available from the slide collection of the UAIC!

On the ground underneath the willows another big green grasshopper, Schistocerca shoshone, was pushing her eggs into the loose sand of a dry part of the riverbed. She belongs to the Orthoptera suborder Caelifera and lacks an ovipositor. Instead, her abdomen can be elongated like a telescope. When she pulled it out of the sand, it was nearly 2 cm longer than her wings. In the image above left it is already partly contracted again. The images on the right were taken hours later and show the normal appearance of this bird grasshopper.

Trimerotropis pallidipennis, Pallid-winged Grasshopper
Eggs that are laid now are most likely be the form in which these grasshoppers, katydids and crickets overwinter. Some of these eggs may even need a cold stimulus to end their diapause and begin their development. But I also saw some young Meadow Cricket nymphs and I know that adults of the most common band-winged grasshopper species shown above can be found all winter long.