By: Kaitlin Poulain
| Photo by Bill Maynard, New Mexico Department of Game and Fish |
(Empidonax traillii extimus)
TAXONOMY: DIMENSIONS:
Class: Aves Length: 5.75 inches
Order: Passeriformes Weight: 0.42 oz
Family: Tyrannize Wingspan: 8.5 inches
Genus: Empidonax
Species: traillii INTERACTION CALLS
Subspecies: extimus
DESCRIPTION:
During spring in the southwestern part of the United States, the air is full with the ripe calls of many bird species, but none have the distinct sneeze-sounding "fitz-bew" of the southwestern willow flycatcher. These birds do not draw much attention to themselves and look so much like other flycatchers the even expert birders have trouble picking one out from a line up. Only by its song, is this bird distinguishable from its fellow flycatchers. However it does have slightly distinguishing appearance. The back and wings have a grayish-green color with an almost white throat, light olive breast, and a pale yellow belly. Each bird has two wingbars and an eyering is either faint or not there at all.
DISTRIBUTION AND HABITAT:
The southwestern willow flycatcher gets it name from the region of the United States that it breeds in. Historically these birds could be found in a range that extended from southern California to western Texas and as far north as southern Colorado and southern Utah. Over the years their range has not changed too dramatically. Most of the range has remained intact except for a little shrinking on the far eastern portion of their range.
These birds prefer dense riparian (along the river) areas to nest in. They like dense trees and shrubs that offer protection. Many of these birds look for rivers, swamps or other wetlands to nest in. Most southwestern willow flycatchers historically nested in native vegetation along the waterways, however has the riparian communities changed due to introduction of exotic species, the flycatchers have begun utilizing the new vegetation in the environment. They now also build open cup nests in non-native trees or hybrid native/non-native trees.
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| Photo by G. Andrejko, Arizona Game and Fish Department |
THREATS AND LISTING:
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| Photo by G. Andrejko, Arizona Game and Fish Department |
One of the biggest threats to the southwestern willow flycatcher is human interference in their environment. For over a century, these birds the faced decline because of livestock grazing, water withdrawal and sprawl. As the native riparian vegetation thins or is removed the flycatchers have less of an opportunity to find the right amount of dense vegetation needed to nest. In addition, although flycatchers can nest in the non-native vegetation, efforts to reduce the amount of exotic species in riparian ecosystems has destroyed alternative nesting options. Because of this, these songbirds become more vulnerable to other birds who prey on their nests. Cowbirds have been known to incubate in flycatcher nests which inhibits flycatcher population recovery. After a petition, and years of lobbying, the southwestern willow flycatcher was listed in the endangered species list by the U.S. Fish and Wildlife Service in 1995. However, due to the lack of interest and lack of popularity among the public, these poor songbirds have been forgotten by administration.
RECOVERY PLAN:
The recovery plan for the revival of the southwestern willow flycatcher lists several steps that could ensure eventual delisting. They include
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| http://www.fws.gov/southwest/es/arizona/Documents /SpeciesDocs/SWWF/fCH2013/Overview_w_Excl.jpg |
- The establishment of Recovery Units and Management Units that will build populations of the species up to a certain criteria customized to the specific area
- Protection from threats that have prevented the species from thriving in the natural habitat
- Minimization of major stressors to the species that occur because of humans
WHAT CAN YOU DO?
In order to help with recovery efforts, those with private land among riparian areas can limit the pumping of groundwater or the thinning of vegetation along the waterways. The flycatchers need the dense vegetation to protect themselves. Supporting the Center for Biological Diversity efforts in species revival is also vital to helping recovery. Much of the recent successes in protecting this species can be attributed to the great work the Center has done. Lending support to the revival of riparian areas is also a good way to help species protection.
Help these songbirds so that the southwestern United States can continue to hear the little "fitz-bews" of the southwestern willow flycatcher each spring.
SOURCES:
It's sad that many species, much like the southwestern willow fly catcher and the bay checkerspot butterfly, on which I did my blog post on, are threatened due to human development and the habitat destruction associated with it. I find it interesting though that these birds nest in non-native vegetation. Well written blog post!
ReplyDelete-Carla Pangan #BIO227Fall2015
Similar problems to the species I wrote about (New Mexico Jumping Mouse) with the habitat problems etc. Unfortunate that restoring it will involve attempting to fight off the bureaucratic local governments and private land owners... I wish them all the best.
ReplyDelete-Mikki Okamoto