Wednesday, May 14, 2014

May 13 (Day 133) - More great New Mexico birding led by Crissal thrasher, and Empids, Empids, Empids!

***If you like discussions of challenging bird ID's, please read on!

Although I have only spent 2 days in the state, I have been thoroughly impressed with New Mexico birding so far. Some of this has to do with the fact that I have added 16 birds to the year list in those 2 days, but a good deal of it has to do with the fact that I am seeing birds that I have rarely or never seen before! Nancy, my Las Cruces hostess from last night, feels that New Mexico does not gets its birding due since it is sandwiched between birding meccas Arizona and Texas. For example, Arizona has many species that can only reliably be found in that state. The same can be said for Texas. There are no species that are only found in New Mexico, but it does share many species with both Arizona and Texas. This helps to explain how even lacking specialty birds the New Mexico state list is in excess of 500 species! 

As a teaser, I saw loads of small flycatchers today. I am going to be discussing their identification below. These birds can be incredibly challenging to identify, so I hope today's post generates some interesting discussion. I have counted both Hammond's and Dusky flycatchers on the year list today, so we'll see how my IDs sit with people. Some might say I absolutely must hear these species to identify them, and I will surely have the chance to do this in the mountains this summer. In full disclosure I have only seen Hammond's flycatcher a handful of times, and before today I had never seen a Dusky flycatcher. We'll come back to this in a few minutes.

Since I had an east wind today and the temperatures were going to top out in the low 70s, there really was no need to start riding at some very early hour. As a result, Nancy and I headed out for a morning walk with hopes of finding the Crissal thrashers that live near her neighborhood. We saw many of the same species as yesterday (Roadrunner, Gambel's quail, etc), and we also added a number of new ones. We found several Curve-billed thrashers (#374), Cactus wrens (#375), Lazuli Buntings (#376), and a single Chihuahuan raven (#377 - I saw lots more of these later in the day). However, the big find of the morning was 2 Crissal thrashers (#378) that we running around exactly where Nancy had predicted we would find them. These birds are very sneaky and could have posed a real bird finding headache. I have only seen this species once before (in AZ), so it was a real treat to watch them dashing around this morning. I did get one record shot of this sneaky species!

Crissal thrasher, complete with bright rufous undertail!

Today's ride took me 65 miles west from Las Cruces, NM to Deming. There was one decent climb leaving Las Cruces, but for the most part the ride was incredibly flat. I also had a nice tailwind for the second half of the ride so it took me less than 4 hours to cover this distance. When I arrived in Deming I had a decision to make; I could stay for the night or press on an additional 60 miles to Lordsburg, NM. I thought very hard about continuing but decided against it for 3 reasons. First, there is going to be more east wind tomorrow so the riding will be similar to today. Second, I am only 2 days from the Chiricahuas. I need to sort out some lodging logistics before I arrive. Having an extra day to do this will help greatly. Third, I found great birding at Mountain View Cemetery in Deming. Al, one of my dinner companions from last night, said it was a great migrant trap and a good place to view flycatchers. He was spot on!

65 miles west to Deming

Flat roadside terrain

I spent 4 full hours kicking around the cemetery this afternoon. There were dozens of Western kingbirds as well as an active Swainson's hawk nest. I saw many Western tanagers and Bullock's orioles, but it was the small flycatchers that really kept me busy. I have never seen so many Empids in such a small area. It presented a great chance to practice identifying these incredibly challenging little birds. Most of these small flycatchers are best identified by voice, but these migrating birds are not calling yet so I had to rely on my eyes to sort out who was who. It is totally possible that I have made mistakes below, but I can take everyone through my thought process as I sifted through countless birds.

Mountain View Cemetery, Deming, NM. These are the
only real trees for miles (see photo above!)

Let's start out with the easier birds. This is a photo of a Western wood-pewee. It is a small western flycatcher with no eye ring and a relatively dark chest. He does have a small patch of pale yellow on his lower belly. He is a bit larger than flycatchers of the genus Empidonax (aka "Empids"). His identification is normally fairly straightforward in regions where Eastern wood-pewee is absent. He is also relatively long-winged and short-tailed.

Next up is this Cordilleran flycatcher. This bird used to be called Western flycatcher before it was split into Pacific-slope and Cordilleran flycatchers. Differentiating these two species by sight is (nearly) impossible, and most people rely instead on range and call to distinguish them. The ranges of the split species can be seen below. This bird initially jumped out to me as it was much yellower than the Pewee and Hammond's/Dusky flycatchers that were foraging in the same area. The next field mark I noticed was the very wide, oval eye ring that is characteristic of both Pacific-slope and Cordilleran flycatchers. Third, the bird has an all pale lower mandible. This knocks out Hammond's, Dusky, and Gray Flycatchers. It was also too small and green to be a Gray flycatcher. In these western regions, Willow flycatcher also has an all pale lower mandible, but Willow flycatcher has only a very faint, round, pale eye ring. Range eliminates Least, Acadian, Alder, and Yellow-bellied flycatchers. None of these species have the characteristic oval eye ring either. Looking at the maps below, it looks as though we can expect this bird to be a Cordilleran flycatcher as Pacific Slope is restricted to more coastal areas. 

Cordilleran flycatcher

OK, now for the really hard ones. Hammond's and Dusky flycatchers are two incredibly similar Western Empids. They are very similarly colored, and most folks instead use shape and body proportions to distinguish them. I was lucky enough to have a decent number of what I presume to be both of these species to study today. Without side-by-side comparison, identification is much more difficult. I am presenting the IDs as I have made them, but again, it is always possible that I am wrong. 

Hammond's is generally a stockier bird than Dusky. Hammond's has a proportionally larger head and smaller bill. He also has longer primary projection which makes his tail look shorter and contributes to his more compact appearance. Dusky has a larger beak and generally appears more long-tailed and attenuated. Both birds have some pale color on the inner half of the lower mandible, and both birds have oval eye rings reminiscent of the Cordilleran. With all this in mind, here are some photos I took of these birds today.

Hammond's-like flycatcher. Smallish beak, decent 
primary projection, short-looking tail

  Another Hammond's-like - bird looks stocky
and relatively compact. Small bill.

Hammond's-like - Very small bill, long primary projection,              Dusky-like - Bigger bill, shorter
short-tailed appearance                                                                       primary projection, tail looks
                                                                                                            longer. Head not as blocky as left.
Dusky-like - Again, more stretched out, less compact.
Bill bigger and tail longer than Hammond's.

Dusky-like. I am the least certain of this bird, but the biggish
beak and the longish tail suggest Dusky to me. 

I am holed up at the Best Western Mimbres Valley Inn here in Deming, NM for the night. Tomorrow  will ride the 60 miles to Lordburg, NM, and they day after I will ride the ~55 miles to Portal, AZ! 

1 comment:

  1. Be careful with these silent empid IDs. Especially since they're unfamiliar species to you and as presented we don't know which photos represent which individual empid (photos of multiple postures are most useful). When identifying Dusky/Hammonds you should also carefully rule out Gray Flycatcher as a possibility. Eliminating Pacific-slope based on range is a matter of probability, a good bet but not guaranteed. Most of your photo captions include the suffix "-like" indicating to me that you're not certain--is adding it to your life list premature? If you're not certain, what's the rush since you'll soon encounter vocal birds of all these species. -Dave