Tuesday, March 25, 2014

Survey Training day 2 - western grebe, lucy's warbler, ladderbacked woodpecker

Didn't have a camera for this one :(

I did a practice survey with Alicia as my guide at Castle Rock, in the Havasu NWR. It was an interesting plot, a wide dry shrubby canyon ending at a marsh, partitioned by its namesake, a large rock formation with steep walls. On the east side of it, a stand of trees, with one especially tall willow which saw a lot of action over the day. On the west side, a crispy tam and mesquite graveyard. The north end was open shrubby desert, we never even made it up there.

We started out listening to a lumpy male Costa's hummingbird sing his tiny kazoo song at the tip of a palo verde right by our parked cars. Then we followed the CH-CH-CH-CH song of a male black-tailed gnatcatcher coming from the east side of the canyon toward the SWEET SWEET SWEET song (recording of a different individual by Lauren Harter) of a warbler (yellow or lucy's??? I still can't tell! Alicia is a good teacher and let me figure it out in my own time) in the stand. On our way over there, we spotted a pair of ash-throated flycatchers and caught the DEET DOOT of a verdin south of us (then we completely stopped listening to them - whoops! others saw up to 7 PAIRS! gotta pay better attention next time!). A raven flew from the east wall to the castle rock, and appeared to be eating something (dirt? water from a tiny pool?) from a ledge.

We tried to see where the pair of ash-throats were going, and walked toward a wall of arrowweed, like a moat around the lush mesquite and willow stand. We knew there was water on the other side of it, but we weren't sure how far. A male gnatcatcher flitted about the arrowweed right in front of us, as if taunting my camera-less disposition (after failing miserably to capture his brethren on film in Blythe last week), and Jenn spotted the female over by the castle rock. I should have paid better attention to make sure they were a pair. I caught a brief glimpse of the aformentioned warbler, grey with a dark red rump patch - a Lucy's! as it dove into a nearby fruiting mesquite. The ash-throat pair were hopping about in the large willow when a male ladder-backed woodpecker showed up, causing a tizzy. The woodie won, the ash-throats dispersing, but not before confusing us because we caught a wiff of a call from behind us in the scrub. Are there more than 2? And how many Lucy's? We only hear one singing at a time. They only sing until the nest is built, so its important to pay attention to their countersinging early in the season!

Deciding we needed a bird's eye view to clear all this up, we begin ascending the side of castle rock, which you should never do in front of fellow crew members watching from below, because they will chastise you as you awkwardly scramble along a sloping inches-wide ledge with a clipboard in your hand and binos swinging across your chest. We ignored them and managed to get up to a fairly stable viewpoint. The view was great, but suddenly the birds shut up and stopped showing themselves. It was only 9:15, seemed a little early for the midday lull. After awhile of looking at coots paddling in the marsh, a strange visual phenomenon of small insects flying up and down in place whose wings only reflected sunlight on their way down, giving the impression of desert snow, and the ladderback not doing much in the willow, a harrier blasted out from behind and soared along the cliff wall then out over the marsh. Perhaps that's why it was so quiet? Then I spotted a raven on a shelf in the cliff wall decorated with white wash and a pile of sticks - a nest! Is it in use now though? The raven slowly ambled along the shelf, then hopped up into the nest and got comfortable! Ravens have enormous territories, so if this were a real survey, it would be best to consider it 25 or 50%, although we did see a few crossing the plot over the course of the morning, meaning the pair or family group were using the area extensively today.

I glossed over the waterbirds, because I need to brush up on them, but also need to not forget about them on the map! Apparently coots ARE territorial and the one we watched swimming with its head held low over the water did not have a stomach ache, but was acting aggressive towards a trespasser. There were two pairs of western grebes, whose mask dips down over its red eyes, but has a similar tinkly ratchet call as Clark's. I thought I saw some pied-billeds, and others say they saw an eared, which only winters here and has a loon-like call. We heard what Rudy IDed as a common gallinule calling from the reeds. It sounds a lot more trumpet-like than the coot, its tone often cracking and bending.

After overhearing an awkward interaction between Bobby and some unseen tea-party fishing enthusiast (handled gracefully by Bobby though), we decided to try the other side of the rock. Some rough wing swallows were flying over the blackened corpses of tamarisk and mesquite, possibly swinging close to nest sites in the cliff, but we never caught a definite landing. We heard 3 gnatcatchers chitting at the same time - which is not considered countersinging, a term reserved for patient communication between rivals, with pauses to listen to neighbors. We ambled towards them, noticing a strange crackling sound emanating from the downed branches at our feet, when we spotted a ladderback on a small burnt snag. Glassing it, I exclaimed, oh its a female! and Alicia responds, uhhh are you sure? when we realized we were both looking at different birds - a pair which promptly copulated for our viewing pleasure! The male then flew to the very base of a thick mesquite bush and began foraging. I've never seen a woodpecker so low to the ground (except the red-bellied's slurping worms from Patterson Park's lawn!). He moved on to a downed branch only a couple meters from our feet, and I watched his meticulous tapping/chipping away at the outer layer of wood to expose a small hole, then use his tongue to flick a fat white grub out of it! This is a real treat, considering they usually do this high up in treetops, far from the view of us landlubbers. While we were watching, we heard a drumming nearby. A rival male? Nope! It was the female, drumming on a burnt section of the aforementioned snag, in somewhat of a fresh indentation. Was she signaling that she would like to create a cavity there? Wish we could go back later and find out!

Ladderbacks are like the downys of the desert. Small woodpeckers with especially contrasting black and white barring on their wings and back, and dusty yellow, faintly spotty breasts. The males have a rouge crest that the females lack, but which both sexes possess when in the nest! They make the familiar PIK! call and squeaky laughing call like hairys and downys of the east.

The pair took off and disappeared on the east side of the castle rock. A Lucy's shot past us with a male gnatcatcher in hot pursuit. The same Lucy's as the east side? How many are there? These are the things I need to pay better attention to for the "real" surveys. The little Costa's was back on his perch when we returned to the lot, zinging away.

I felt a little less overwhelmed today than yesterday, but there was a LOT that I missed! Apparently violet-green swallows and white-throated swifts were seen foraging overhead and even approaching holes in the cliff walls. I practically ignored the waterbirds out of ignorance, but rather than forget about them, I need to remember to take notes, recordings, and look them up when I get back to the field house.