Arizonans keep watchful eyes on bald eagles nesting near humans

RIO VERDE – Across Arizona, humans are keeping a sharp eye on bald eagle nests that are close to areas with high recreational traffic. As part of a program run by the Arizona Game & Fish Department, these nestwatchers monitor the behaviors of the eagles and make sure their treetop and rock ledge nests are safe.

The Arizona Bald Eagle Nestwatch Program began in 1978 as a volunteer organization to monitor breeding bald eagles. Today, the program is so popular people are on waiting lists, and the watchers get paid to do the job.

Wildlife officials say the program and other efforts to protect our national symbol are paying off: There now are eight times as many bald eagle nests as there were in 1978.

“This is a project that I am enjoying a lot, and I want to do it for many years,” said Eduardo Martinez, who has been an Arizona nestwatcher for five years.

Martinez and his wife are watching a pair of eagles nesting about a 10 minute walk into the desert near Box Bar Recreation Area in the Tonto National Forest, near Bartlett Lake.

“I love this place. I’ve been to several places, and several nests all over Arizona,” said Martinez, who comes to Arizona from Mexico yearly to watch the eagles. “And this place, I think, has the most diversity.”

Nestwatchers start in February, keeping an eye on 10 to 15 breeding areas that are in busy recreational areas. In some breeding areas, including sections of the Verde River, areas have been closed so nests aren’t disturbed.

Arizona has close to 90 bald eagle breeding areas, according to Game & Fish. The agency notes on its website that nestwatchers can help identify eagles that are in life threatening situations so biologists can help.

The watchers work 10 days in a row, spending those days and nights near the nests to keep close watch. They spend their time talking, reading and, of course, watching the birds.

“By having the nestwatchers here, we’re able to figure out what might be causing problems and make sure that we’ve got management on the ground, and recreators that understand the proper way to recreate in an area where you might have a bald eagle’s nest just right behind you,” said Kenneth Jacobson, who’s the bald eagle management coordinator with Arizona Game & Fish.

Nestwatchers spend so much time with these birds they start to pick up on personality traits. Martinez said 2019 was a “complicated” year for the bald eagles he watched. Food was scarce, and one of the fledglings died.

Kenneth Jacobson, who’s a bald eagle management coordinator with the Arizona Game & Fish Department, trains a telescope on a bald eagle nest. He says there’s been “significant growth” in Arizona’s bald eagle population since 1978, when there were only 11 breeding pairs in the state. (Photo by Isabella Hulsizer/Cronkite News)

“That’s nature,” Martinez said. “But because we put names on them and we were really attached to them, one of them dying was a really sad moment for us.”

Martinez said he’s still debating whether to name any fledglings that hatch this year.

Last year, the breeding season was equivalent to a soap opera at a nesting site near Lake Pleasant – and thanks to a remote camera set up by Game & Fish, the public got to watch.

First, a rival ousted a male and bred with the female, who laid three eggs – all of which were eaten by ravens and ringtail cats. There was hope for the fourth egg, but the mother destroyed it, perhaps because she sensed an abnormality, Game & Fish said.

A breeding pair has returned to Lake Pleasant this year, and they’ve built a new nest high up on a rocky ledge. The first clutch of eggs was lost to predators, likely ravens, but Arizona Game & Fish said there’s still time for another clutch.

Jacobson said overall the bald eagle population in the state continues to climb.

“Back in 1978, when bald eagles were listed as endangered on the Endangered Species Act, we only knew of 11 breeding areas in the state,” Jacobson said. “Now, in 2020, we’ve got 90 breeding territories across the state. There’s been a significant growth in the population.”

Last year, Game & Fish said 71 eagle eggs hatched, down from 87 in 2018.

The department expects this year’s eggs to hatch about the end of March and early April, and it will tag the fledglings. In three to four years, the birds will be ready for their own breeding season.

Game & Fish has a 24/7 live stream of the bald eagle nest at Lake Pleasant, but it’s not as close as last year’s camera because of the nest’s location.

This story is part of Elemental: Covering Sustainability, a multimedia collaboration between Cronkite News, Arizona PBS, KJZZ, KPCC, Rocky Mountain PBS and PBS SoCal.

Climate Change Is Decimating Bird Populations in the Mojave Desert

LOS ANGELES – We found out last year that hotter, drier weather due to climate change is likely causing bird populations in the Mojave Desert to collapse at an alarming rate. A new study suggests one big reason why: Birds are having a hard time staying hydrated, which means they’re having a hard time staying cool.

Over the past century, temperatures in the Mojave Desert have risen about 3.5 degrees Fahrenheit, while precipitation has declined in some parts. That’s coincided with a roughly 40% decrease in the number of bird species documented there.

Adapting has been harder for some birds than others.

“Birds that required more water over the last century to cool off experienced more decline in the desert,” said Eric Riddell, postdoc in museum of vertebrate zoology at the University of California, Berkeley and co-author of the paper. “If birds had an unlimited amount of water they could probably deal with a lot more heat.”

The water requirements for desert birds are increasing as heat increases. (Courtesy of Eric Riddell at UC Berkeley )

Different species of birds get water in different ways.

Birds with primarily plant-based diets hydrate by eating seeds, some insects and by drinking from pools of water.

Primarily carnivorous birds, on the other hand, hydrate mostly by eating other animals, and don’t tend to drink from oases. The problem is that they have to hunt in order to eat, which means expending lots of energy in increasingly hot environments.

“Compared to 100 years ago, some birds needed to collect up to 60 more bugs per day just to replenish their water reserves,” Riddell said. “So that extra cost per day of having to go out and find a little more bugs and a little more bugs, we suggest has contributed to the collapse of the desert bird community.”

Larger birds with high energy demands have an even harder time. The daily grind can lead to a decline in reproductivity and premature death.

Birds like the American kestrel, prairie falcon and turkey vulture have all suffered.

The authors estimate that there’s been a roughly 10% to 30% increase in water requirements for desert birds over the past century. That need could increase by up to 80% by 2100.

Related story

Beetles vs. birds: What happens when fighting nature with nature backfires?

To estimate how bad things could get, the researchers created computer models of 50 different types of desert birds, all of which they subjected to increased heat due to climate change. Thirty-nine of the species declined significantly.

“For people that want to go out and see these birds, not only will they see fewer of them, but they will have much smaller windows of time when they can see them,” Riddell said. “Not only that but the conditions that make the desert hard to live and be active in for birds will also be true for humans, as well.”

A separate, larger study published earlier this month estimated that 3 billion birds have disappeared from North America in the last 50 years.

Beetles vs. birds: What happens when fighting nature with nature backfires?

COTTONWOOD – Fighting nature with nature seems like a good idea – unless nature doesn’t care about geography.

The U.S. Fish and Wildlife Service listed the southwestern willow flycatcher as endangered in 1995. There are an estimated 600 to 800 breeding pairs of the songbird scattered across the West. (Photo courtesy of Natural Resources Conservation Service Colorado, USDA)

Today, the effects of a federal decision made 20 years ago to use Asian beetles to slow the spread of an invasive shrub across the West are reducing nesting habitat for an endangered songbird – the southwestern willow flycatcher.

The U.S. Department of Agriculture’s Animal and Plant Health Inspection Service, introduced tamarisk leaf beetles from China and Kazakhstan around the West to kill tamarisk trees, also known as salt cedars. Some of the beetles were released near Moab in eastern Utah.

“The goal of their program was to control tamarisk,” said Greg Beatty, a biologist with the U.S. Fish and Wildlife Service who has led flycatcher recovery efforts since 1999. “Reduce it. Kill some plants. I don’t think they anticipated that it would kill all tamarisk, but that it would reduce its abundance.”

The beetles did their job, stripping the tamarisk of its feathery, green canopy, which often kills this fast-growing deciduous shrub. The tamarisk was introduced in the 1800s from Eurasia as an ornamental, for use in windbreaks and as a way to control stream-bank erosion.

The APHIS program wasn’t supposed to release beetles within 200 miles of where southwestern willow flycatchers nest. The birds can be found throughout the West; in Arizona, around Roosevelt Lake and along the upper Gila River. Experts calculated even if the beetles migrated south toward Arizona, the bugs would not survive the difference in climate.

But beetles don’t follow rules.

Tamarisk trees, which aren’t native to the Western Hemisphere, can be found around water in Arizona, including Roosevelt Lake east of Phoenix, where flycatchers have been found. (Photo by Rachel Charlton/Cronkite News)

“In retrospect,” Beatty said, “seems pretty clear there wasn’t really any type of geographical boundary that would have kept them where they were at.”

From the Virgin River in southwestern Utah and into the Grand Canyon and its tributaries, the beetles spread into Arizona, Beatty said.

“It’s happened faster than anybody would have expected because we didn’t expect them to be here,” he said.

Tamarisk is reviled across the West. It is notorious for crowding out native vegetation, effectively choking riparian areas, particularly along dammed waterways. Some scientists say it hogs water, leaving less for native species, although that’s in dispute. It’s considered a noxious weed in New Mexico, Montana, South Dakota, Wyoming and Texas.

The USDA terminated the biological control program in 2010. But now there’s concern over what will happen to flycatcher habitat in Arizona.

The primary nesting habitat for the flycatcher, which was listed as endangered in 1995, is in willow trees surrounding riparian areas. However, researchers have found that flycatchers also use tamarisk.

Robin Silver, co-founder of the Center for Biological Diversity in Tucson, said flycatchers depend on foliage to protect their nestlings from the scorching Arizona sun.

“Even if there are willows, they’re still dependent on the salt cedar or the tamarisk,” Silver said. “So to denude or kill that tamarisk right now is really putting too much on the flycatcher for them to be able to survive long term.”

The songbirds – which are brownish-gray with white wing stripes and measure about 6 inches from beak to tail – are also faithful to their nesting sites, returning year after year.

The birds still are listed as endangered. In an email, Beatty said the flycatcher population is measured by territories, which include southern California, Arizona, and New Mexico. There are 1,200 to 1,600 territories, and the U.S. Fish and Wildlife Service estimates there will be a breeding pair per territory. That puts the number of breeding pairs at 600 to 800.

The Center for Biological Diversity successfully sued APHIS in 2013. The court’s ruling found that APHIS did not comply with the Endangered Species Act in the conservation of an endangered species.

APHIS declined to comment for this story, but the agency did provide documents that state the “greater than anticipated natural and intentional human-assisted movement of the beetle caused it to spread into flycatcher habitat.”

As for the future of the flycatcher, Beatty is concerned that habitat loss will have significant impacts.

“I think we’re going to have greater booms and busts … the status of the population will decline as the beetle expands throughout its range.”

Caltech scientist uses drones to herd birds away from airplanes

LOS ANGELES – The danger birds pose to airplanes is no joke.

In the past four years just at Los Angeles International Airport, birds and other wildlife hit aircraft more than 500 times, according to Federal Aviation Administration data.

At Phoenix Sky Harbor International Airport, wildlife hit aircraft more than 230 times from August 2014 to this August.

And remember, it was a flock of geese that forced Capt. Chesley “Sully” Sullenberger and co-pilot Jeff Skiles to land their Airbus 320 on the Hudson River in 2009. All 155 passengers and crew aboard survived.

That famous bird strike got a California Institute of Technology scientist thinking about a high-tech solution.

Aerospace professor Soon-Jo Chung was troubled that it came down to the pilots’ skill to save Flight 1549, which had just left New York’s LaGuardia Airport.

“It made me think that next time might not have such a happy ending,” Chung said in a news release from Caltech.

He and his colleagues worked on an algorithm that enables a single self-guided drone to herd flocks of birds away from an airport.

The algorithm is based on a study of flock dynamics, where each bird influences the movement of the next. Chung’s idea is to have a drone fly close enough to a flock to steer it away from an airfield, but not so close that the birds scatter and become a greater risk to planes.

It’s not just theoretical. They’ve tested it with drones and birds near a field in South Korea. But no airport has adopted the technology so far.

It’s potentially a big leap forward. At LAX, crews still cope with birds the old fashioned-way, using traps and car horns.

“They drive the car all over trying to find birds or flocks of birds, and if they see some that are on the ground, they give them a toot and off they go,” said Keith Wilschetz, deputy executive director for operations and emergency management at LAX.

At Sky Harbor, a wildlife biologist helps keep these strikes at a minimum. Employees patrol the airfield “around the clock” to identify hazards, and they employ bioacoustics – vehicle horns and pyrotechnics that emit “a high screeching sound or a detonation sound,” according to an email from airport spokesman Gregory Roybal.

He said the airport mixes things up so the wildlife doesn’t get a chance to become acclimated to their methods. Crews also reduce water and vegetation, which attract wildlife, around the airport, Roybal said.

When such solutions fail, it’s costly, not to mention potentially deadly.

At LAX, the strikes over a four-year period caused $1.7 million in damage, according to the FAA data.

The most expensive LAX bird strike was when a Clark’s grebe hit a Quantas Airlines 747 in 2016. Damages: $1.5 million. That same year, a hoary bat did $200,000 in damage to an Airbus 320 passenger plane.

Birds of all kinds collide with planes – from the Acadian flycatcher to the yellow-rumped warbler – but in most cases the breed is simply unknown. Why? Because there’s not much left to analyze.

Cronkite News reporters contributed to this article.