Thursday, 16 June 2016

Lowland Riparian Rarities

Nevada Bird Count Tour 4 Part 3 and Tour 5 Part 2

Two of the major projects the NBC is involved in occur along the riparian corridors of the Walker and Truckee Rivers. Characterized by massive, gnarled cottonwoods and dense thickets of willow, buffalo berry and Russian Olive, these riparian zones are absolutely loaded with birdlife. Most of these birds are quite common and not that exciting on their own, but the sheer number of wrens, kingbirds, doves, towhees, sparrows, orioles, hawks, grosbeaks, blackbirds and owls combined is always impressive. While surveying these sites it’s not uncommon to have to scribble in extra birds in the bottom margin of our 25 line datasheets, and it provides great experience at taking in a huge amount of information at once, then subsequently ignoring while still keeping track of all the birds you’ve already recorded, while watching and listening for new ones later in the count. Plus, every once in a while you get something exciting mixed in.

Shrubs and small cottonwoods at Rafter 7 Ranch

Cottonwood gallery below Weber Reservoir

On May 29 near the end of our fourth tour, Ned and I headed out towards the Weber Reservoir to complete a couple transects. Mine was LowerWeber, and followed the river along a gorgeous cottonwood gallery below the reservoir. Seeing all the campers along the opposite side of the river for the Memorial Day weekend took a bit out of the atmosphere, but the area was still super birdy. Many Common Nighthawks were flying around well into the morning as they seem to do quite often in these areas, and Wood Ducks in the river were nice to see.

River along LR-LowerWeber

My most interesting bird of the morning was a raptor I heard vocalize while doing veg on my way back. It first reminded me of a raspy goshawk, but goshawks are only found up at higher elevations, and it didn’t sound quite right anyways. While Cooper’s call is more nasal than a gos, this bird didn’t seem right for that either, so I decided to let it go unidentified. A short while later a large, brown falcon buzzed down the river corridor, and with the quick look I assumed it was a Prairie, the regular large falcon in the Great Basin. But then I put two and two together and realized it was a juvenile Peregrine! It’s a bird I’ve very rarely had to ID by ear, so it was a fun learning experience. Funnily enough, when I was doing a raptor set for a birding by ear course this past winter with the University of Guelph Wildlife Club, I had decided to exclude this species because they’re not something I’ve heard vocalize very much at all. But when the class insisted I include the species, listening to the tapes on the spot I had described the call as a raspier goshawk. Glad my first impressions of its call were the same in both instances, I just need to remember it for the next time!

The next day Kala and I had a double-observer survey at Mason Valley WMA, a local birding spot just north of our Yerington field house. Many of the same birds were had a this site, although the river here is shrubbier for the most part than the open cottonwoods of Lower Weber, so we had many more Spotted Towhees and Bewick’s Wrens which love the dense thickets.

Mason Valley WMA

Breeding Western Bluebirds are always fun to see out that way, and some migrant Western Tanagers and Plumbeous Vireos added some burry phrases to the chorus. Mason Valley is also home to a large system of ponds and wetlands, so we had my first Caspian Tern and American Bittern as flyovers on some of our counts. But we had our best bird of the morning as we were approaching Point 7, a loud, emphatic song that no Easterner can forget and no birder can dismiss, “TEACHER TEACHER TEACHER TEACHER.” An Ovenbird! They are a regular rarity in the Nevada, with five records just last year along according to eBird (and the species is not on the state review list). However, looking it up afterwards I found that this was the only record in the state this spring, so that was exciting. The bird decided to inconveniently stop singing during the ten minute duration of our count, but gave us a few good bouts of its unmistakable song before and afterwards. I had missed the Zone-tailed Hawk a few days before I arrived, the Rose-breasted Grosbeak that Ned had down at Warm Springs and the Acorn Woodpecker Kayla had in the Pine Nuts, so this was my first rarity of the season.

Fast forward to our fifth tour, after spending a couple days in the Pine Nuts Dave, Ned, Kayla and I descended onto Rafter 7 Ranch where I have my area search to knock out the 3 transects on the property. Rafter is notorious for its dense, dense thickets, and transects with randomly located points that one must get to.

View from Rafter7B Point 6

But for a some of the points you can walk along the salt desert and then cut into the thickets closer to the point.

Salt desert bordering Rafter7B

As Kayla and I walked to the southern-most transect which we were splitting, we noticed we were following a nice set of Mountain Lion tracks. My area search is on the same ranch a couple kilometers north of this transect and I hadn’t seen any cat sign there on my many visits, but here the tracks were very apparent going both directions in many of the open sandy areas next to the riparian zone. Because she has some stupid luck with these animals, Kayla actually heard a cat giving some gruff noises on her end of the transect after we'd split up for our surveys, her second of the season! In two seasons out here I still haven’t had sight or sound of one, but I’ve still got a month and a week to go so I’ve got my fingers crossed.

Mountain Lion prints

My half of the transect had a couple Blue Grosbeaks as well as more numerous Lazuli Buntings and Yellow-breasted Chats, three species that I find more often at Rafter than most lowland riparian areas because of its such good shrub habitat, but other than that it was the usual suspects. Since we only had 5 points each to do and all of the veg on the ranch we had done with the crew last season (now that was an endeavor!), we headed out early with the windows down and the quirky local Classic Rock station on the radio. As we were passing through a cottonwood stand, an incessant, snappy song caught my ear over the radio. Hold on, really?!? I stopped the truck, turned off the radio, and the “che-bek che-bek che-bek” of a Least Flycatcher came in through the driver’s side window from the grove right off the road. We got out and got great views of the bird singing and flying from perch to perch. Kind of fun to get excited about these dirt-common eastern birds while one’s out West! It turned out that this bird was a bit higher quality than the Ovenbird too, with only 9 accepted records for the state in addition to another 4 or 5 of silent fall birds that didn’t make it past the NBRC. Here's a super-shaky video of the bird singing.

So amongst the hordes of common river birds one can pick out some stray jewels if they keep their ears open, and having an Easterner’s ear certainly helps when getting rarities here in the West. The next day I was back at Rafter 7 for my area search, then the whole crew immediately headed up on the long trek to Black Rock/High Rock to round out the tour.

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