Olivaceous Thornbill (Chalcostigma olivaceum)

Olivaceous Thornbill (Chalcostigma olivaceum)
Originally uploaded by rgibbo3

I finally got an OK photo of this outstanding bird. The Olivaceous Thornbill is one of two hummingbirds I see regularly in my study sites. This field season I had the help of two Peruvian botanists; they were extremely knowledgeable and answered all my pesky questions. The small red flowers in the photo are one of three species of Gentianella; each of the three species has a different color: red, fuschia, and purple. Every time I found Olivaceous Thornbill, there was a patch of Gentianella close by. I believe this and insects are the majority of its diet.

There are reports of this species walking, but in the twenty or so times I've seen it, it has always fluttered rather clumsily from one flower to the next alighting on the ground. I would really like to see a video clip of this species walking.

Although you can't see it in this photo, the male has a narrow gorget that shimmers a brilliant spectrum of colors if at just the right angle. I'll have to keep trying for that shot.

Stuck in Lima? Go birding.

The logistics of putting together a small, but involved, expedition sometimes means downtime. Maybe it's permits, transportation, team members, etc. that has you hung up. What to do with all that spare time? Write grant proposals, check. Review grant paperwork, check. Annoy friends with instant messaging, ad nauseum. One could explore Lima, the "Pearl of the Pacific". Seen it, done it.

A couple of weeks prior to departing the US, I discovered an old birding acquaintance from Texas, Steve Gast, was working in Peru. He had posted on the Birding Peru list-serv about seeing White-throated Earthcreeper in Lima Department. White-throated Earthcreeper is a cactus/scrub specialist and inhabits a narrow elevational band that supports this vegetation community. The reported location was about 200 km north of the known range and it's not the easiest identification. On the other hand, Steve is no slouch and he wouldn't stick his neck out with a post like that without being 95% and giving a possible out.

Enter Gibbons to help get the last 5% of uncertainty dispelled.

I would be in town just at the right time to accompany him for an evidence gathering mission. I brought my camera and he brought his recorder. We set out at 5 AM from Lima for the three hour trip up the pacific slope. We passed through some of the driest, barren land on the planet and after climbing in elevation for a few hundred meters cacti began to show up. We got out to stretch our legs and have a look and listen. From the valley wall road we could hear a chorus of cricket chirps bouncing around the valley. Finally Grayish Miner and Cactus Canastero were heard and then seen and we spent some time trying to get a look while we waited for the cloud bank above to lift. After a little playback, Cactus Canasteros were seen. These were new for me and they look a lot like other Asthenes, not much different at first impression.


We hit a patch of vegetation that was boiling with birdsong: Yellow-billed Tit-Tyrant, White-browed Chat-Tyrant, Mourning Sierra-Finch, Band-tailed Sierra-Finch, Band-tailed Seedeater, Long-tailed Mockingbirds, Bare-eyed Ground-Doves, Collared Warbling-Finch, and Great Inca-Finch come to mind. The Great Inca-Finch is one of five Incaspiza species, which are all endemic to Peru. How they all managed to get their own restricted ranges would make a nice project if it hasn't already been done.

Onward and upward to the target species we went and sure enough, the second we stepped out of the truck, a rusty blur darted below the road below. We had all the time we needed with these cooperative birds.

The field marks are rusty coverts and secondaries, a broad supercilium, and shorter, stouter bill than U. jelskii. Check, check, check. The song was spot on for the recording we had and it responded by flying right in and perching on a cactus plant.

White-throated Earthcreeper is in the Least Concern category according to the International Union for the Conservation of Nature. The reasons they give for this are the size of the range and the likelihood that the species numbers are greater than 10,000 individuals. Steve's discovery means this species is more widely distributed than previously thought and so it's even less likely to be uplisted to threatened. This species appears to have a strong habitat preference for sparse scrublands with cactus (not sure of the species) and this habitat isn't currently under heavy development pressure.

With all the documentation we needed, we climbed a little further up the mountain and finally called it a day.

So if you're stuck in Lima, go birding.

Miraflores, Mira Aves

I'm back in Lima, Peru staying at the South American Explorers clubhouse in the Miraflores district while permits are processed and preparations completed for a nine-week expedition. The clubhouse is an outstanding base of operations with strong coffee in the morning, loads of maps and information in the library, and wireless internet. I have a permanent link for the South American Explorers below.

In between making copies of permit packets for INRENA and gathering supplies I took my camera up to the rooftop, ideally situated next to a tree. I managed to record about 15 species in less than an hour.

It's hard to miss Rufous-collared Sparrow (Zonotrichia capensis) with its clear sweet song sounding out most of the day. This bird species was the subject of Zac Cheviron's dissertation. Dr. Cheviron found a genetic break between highland and lowland Z. capensis populations with the break occurring around 3800 m. Phred Benham told me the city birds have a different song than the country birds, the city birds lack the trill. These Miraflores birds certainly lack the trill.

Another ubiquitous and vocal urban bird is the Blue-black Grasquit (Volatinia jacarina). I learned something today from the new Birds of Peru field guide. The Pacific coast males of this species rarely are completely blue-black. Instead, they stay in a mottled plumage. I would have chalked it up to a young male molting into its big boy duds, but apparently that doesn't happen. I wonder what that's all about. Was it some random drift effect or was selection involved?

Polymorphic species have fascinated me for years. I recall trying to wrap my head around white morph and reddish morph Reddish Egrets and how the morphs might have evolved and how they could be maintained. It hasn't been resolved and I'm sure some molecule-oriented bird nerd will give it a crack one day.

Doves are everywhere in Lima and these three are easy to find and photograph. If you are familiar with North American birds, you won't have to stretch your ID skills too much with these three. The Eared Dove and West Peruvian Dove are both in the genus Zenaida like our Mourning Dove and White-winged Doves. These two are analogs to Mourning and White-winged. Even their vocalizations are reminiscent. The third dove is the Croaking Dove, aptly named because its vocalization is a repeated low gravely "wow".

I submitted an eBird report for a half hour of rooftop birding, my first Peru submission to eBird. Highlights for me were Peregrine Falcon circling around looking for a dove dinner and an Osprey cruising south. The Osprey is a Nearctic breeder that winters along the coast here in Peru. I wonder if it's starting to get that migratory restlessness.