by Gail Garber
A Species in Decline
Two years ago in Aloft magazine, we featured the plight of North America’s smallest falcon, the American Kestrel, also casually known as the sparrow hawk. It is a strikingly beautiful bird about the size of a Mourning Dove. Males and females have different plumage, making them easy to identify. Breeding bird survey data show steady population declines across the continent, with some areas steeper than others. Throughout North America, populations have declined by 47% between 1966 and 2010, with the steepest decline, 88%, occurring in New England and the Mid-Atlantic coast. During that same time period, the Rocky Mountain/Colorado Plateau region, our back yard, experienced a 64% decline. Based on these long-term data it appears that the kestrel may become extirpated in some areas if actions are not taken to reverse the decline.
The causes of the decline are unclear. However, the primary suspect is habitat loss. Kestrels require both grasslands in which to hunt large insects and small rodents, and cavities for nesting. These might be dead or decaying trees with a cavity carved out by a woodpecker, a natural cavity on a cliff or arroyo wall, a crack in a bridge or other structure, or your old shed that has an entrance hole beneath the eaves.
Kestrels lose habitat when our cities expand, where houses and stores are built, and when open fields are converted to parking lots and other human uses. They also are at risk when formerly open fields are converted to forests, or large trees desirable for their shade are planted in backyards and neighborhood parks. Often, in the southwest, the planted trees are cottonwoods (Populus sp.) and the exotic volunteers are Siberian elms (Ulmus pumila). When these trees mature, which they quickly do, they often become home to a family of Cooper’s Hawks.
Cooper’s Hawks find the smaller American Kestrels easy prey, especially snack-sized fledglings that have
not yet fully developed flight skills and a wariness towards the larger predator. The Cooper’s Hawk population has expanded rapidly in the southwest and, in the Albuquerque area, it is the most common nesting raptor, with one in just about every single park and home with a large tree. In the Middle Rio Grande bosque, they comprise over 80% of all the nesting raptor species. Although the aging cottonwood forest along the mighty Rio Grande provides a wealth of cavities, it is quite rare to find any nesting American Kestrels. Bosque nesting raptor surveys conducted from 2004-2013 documented a total of 18 active nests (2.7%), from a total of 666 raptor nests monitored during that period.
It Takes a Village
The Peregrine Fund was the first major conservation organization to raise the alarm, and established the American Kestrel Nest Box Project, which Hawks Aloft (HAI) joined immediately. Initially, we worked with our friends at the New Mexico Falconer’s Association, who provided us with 12 nest boxes. Most of these were installed at or near Title 1 schools participating in our Living with the Landscape program. However, PNM’s Silver City service center took some of those boxes too, installing them on non-equipment poles in the expansive grasslands found south of Bayard, NM and north of I-10.
We have enjoyed a partnership with PNM since 2002, working on a variety of conservation efforts to reduce avian mortalities, raise awareness among utility companies in the southwest, develop and implement conservation education programs in public schools, and create habitat for wildlife. John Acklen, long-time HAI Board Chairman and Amy Miller, both movers and shakers at PNM, New Mexico’s largest investor-owned utility, joined me about a year ago to think about what we collectively could do to address the issue of American Kestrel declines.
They, and others at PNM enthusiastically supported our fledgling idea! Before long, it was a fully-fledged plan funded by PNM, with a goal to build and install kestrel nest boxes in PNM service territories. The New Mexico Falconer’s Association (NMFA) joined our efforts, and brought other ideas to the table as well. Not long after our initial meeting, PNM, which also owns Texas-New Mexico Power (TNMP), based in various parts of Texas, suggested we also implement the program in that state. Paul Domski, president of NMFA, suggested we contact the Texas Hawking Association (THA), and our partnership grew immeasurably. Steve Oleson, president of THA expressed enthusiastic support and PNM expanded funding levels to encompass the needs of the two states.
Build It, But Will They Come?
Our goal is ambitious – a total of 100 boxes between New Mexico and Texas before April 2015! With PNM funds in hand, we got to work. While THA and NMFA constructed boxes, Mirinisa Stewart-Tengco, HAI intern, and Lisa Morgan, HAI Raptor Rescue Coordinator, got to work compiling a raptor identification booklet that ultimately would be printed on sturdy card stock, and of the exact size to fit into the glove box of every single PNM and TNMP service vehicle. We also developed a PowerPoint presentation that featured falcon identification, detailed the plight of the American Kestrel, its specific habitat needs, nest box placement and installation specifics.
In September, we rolled the program out simultaneously to service centers in both states. PNM and HAI staff conducted trainings in New Mexico, and THA and TNMP staff worked in Texas. The reception was amazingly positive, perhaps thanks in part to the live American Kestrels and other avian ambassadors that captured the imagination and attention of the combined utility crews. There are few humans that can resist the charm of a live raptor in the classroom, adults and children alike.
Nest boxes were distributed at several service centers. Now, it is up to the line crews to select sites in appropriate habitat that are more than ¼ mile from a roadway (to reduce vehicle strikes) and install the boxes on non-equipment poles, below the worker-safety zone, approximately 20-30 feet high. The location of each box will be reported to Stephen Saletta, GIS specialist and environmental scientist at PNM, and a map created that shows the nest box locations.
Everyone has done their part. For the 2015 nesting season, 100 new nest cavities will exist in grasslands and shrublands in the two-state area. All that remains is to see if kestrels agree with our human determined conditions. Stay tuned!
We thank our partners and collaborators on this project:
PNM staff, John Acklen, Bobby Arnett , Jim Consola, Wilson Guin, Claudette Horn, Roger Larson, Amy Miller, Isaac Padilla, Cory Plant , Stephen Saletta, Bobby Sanchez, Jennifer Scacco, Dale Stevens, Lorne Wofford, Jeanette Yardman. Santa Fe, Las Vegas, Ruidoso, Alamogordo, Deming, and Albuquerque linemen
TNMP: Jeff Blitch (Irby), Jerald Breaux, Ed Finley, Bob Fuller, Vincent Herrera, Mike Piscacek, David Shelton, Robert Walker. Friendswood, West Columbia, and Clifton linemen
New Mexico Falconer’s Association: Paul Domski, Greg Rabourn
Texas Hawking Association: Mark Griffin, John McCormack, Steve Oleson, Chuck Redding
Hawks Aloft, Inc.: Gail Garber, Trevor Fetz, Lisa Morgan, Mirinisa Stewart-Tengco