A Tame Approach to Your Airfield Wildlife

June 27, 2018
Wildlife issues can be addressed with access to resources and working with your community.

At the North Little Rock Airport (ORK) in North Little Rock, Arkansas, staff faces a variety of challenges with wildlife.

Clay Rogers, director of ORK, said the airport occupies about 800 acres of land, with a couple hundred of which it wooded. This provides habitat for deer, birds and coyotes.

“We even have an issue with beavers damming up the drainage system and building up ponds that are attracting the deer from the wooded area to the heavier brush area,” he said. “So wildlife is a pretty constant headache.”

Rogers said there hasn’t been a deer strike while he has been at ORK, but they have happened in the past. With the animals on the airfield, there’s always a concern about it happening.

“We recently had an episode with deer on the runway and a member of the FAA safety team that flies out of here sometimes was taxiing and about to take off and there were deer on the runway,” he said. “She tried to go by them and rev up the engine, but it didn’t seem to faze them so she was going to go to the other runway and they just migrated to the other side when she was going to take off there. They seem to be less afraid of people and air traffic noise.”

ORK is trying to clear out a marshy area of the airfield to mitigate the wildlife issue. Rogers said they want to cut it short enough to maintain it with a Bush Hog so it deters deer.

Rogers said the airport has worked with a consultant and the Army Corps. of Engineers to make sure the area is not a delineated wetland or stream know as a part of the waters of the U.S.

Joel Ward of Lyrata Consulting LLC, of Mayflower, Arkansas performed the consulting work.

“The deer are crossing from the wooded area to wetland/grassy area to lie down and get water,” he said. “And we aren’t able to clear that until it gets OK’d by the Army Corps. of Engineers, which is an incredibly slow process.”

Rogers said he doesn’t expect the change to solve all the issues if it’s approved, but it will give deer less of a reason to cross the runway and keep them back in the wooded area of the airfield.

ORK obtained a wildlife degradation permit through the Arkansas Game and Fish Commission, but the airport is surrounded by neighborhoods, so Rogers said deer can only be shot from specific directions in specific areas.

He said the airport has looked at fencing, but the area is very large so to build something large enough would be cost prohibitive.

Rogers said ORK has deer cameras set up to monitor the wildlife and see what efforts are working or not keeping them back in the woods.

“If our maintenance guy sees deer or coyote while he’s out mowing he tries to go by them and scare them off back into the woods,” Rogers said. “We have multiple deer feeders back in the woods that we try to keep them deeper in the woods away from the runways.

The airport also has an issue with coyotes chewing on equipment. The animals are chewing on wiring and even the silicon joint seals between concrete slabs.

“As we’ve done some concrete work separate to the coyote problem we’ve been using rubber rather than silicon,” Rogers said. “That seems to be helping with the areas that coyotes have been coming out and chewing on.”

A North Little Rock police officer is in charge of ORK’s wildlife degradation permit while off duty. It allows him to hunt the deer, reload the feeders and keep on top of the permits as opposed to the airport needing to handle the issues.

“He has been studying beaver trapping and looking at YouTube videos, he has done research on coyote trapping and hunting,” Rogers said. “It has been nice to have Lt. Honeycutt focus on that and be in charge of that for me because it can be its own job of moving feeders and cameras and checking the footage and getting deer feed and taking the time to research and study how to handle the animals that he’s not already familiar with hunting.

ORK also hired a coyote trapper recommended by the game and fish commission.

“The airport managers in Arkansas have all been really good about sharing information and helping each other out as an aviation community,” Rogers said. There has been a good resource for asking other airports and finding resources for what can help.”

“He does it in a way that we’re comfortable with. He’s overly cautious, which we prefer because we want to obviously be overly safe when shooting a gun at them,” Rogers said.”

A PURPLE MARTIN PROBLEM IN TULSA

Tulsa International Airport (TUL) found itself with a major challenge in 2017 after thousands of purple martins decided to take up residence at the airport.
Donald Wyatt, airfield operations manager with TUL, said the birds normally roost in the downtown area of Tulsa when they migrate to the region in late summer, but for some unknown reason were drawn to the airport in 2017.

“We used a lot of pyrotechnics to keep them away from the runway, we tried using lasers,” he said. “When they would come in for the evening about 30 minutes to an hour before sunset we’d be out there with numerous ops staff and our biologist out there using pyrotechnics to try and scare them away.

“Eventually they would get into the trees and that’s where they would stay.”

The campaign to remove the birds also caused issues with outside groups who Wyatt said thought the airport was trying to harm the birds. He said the airport tried to work with them and share the certified wildlife plan and how the airport was trying to protect aircraft from bird strikes.

“We did have a couple bird strikes that were from purple martins,” Wyatt said.

TUL is gearing up for a potential return of the birds this year. Wyatt said they’re preparing pyrotechnic gear and lasers again and the airport has removed some trees.

Wyatt said the airport had issues with hawks as well due to a warmer winter. The birds don’t continue migrating south when it wasn’t getting below freezing enough in Tulsa, so the airport would trap them.

The airport is using a new type of screamer with silver sparkles behind it, which Wyatt said has shown the hawks don’t like.

They also used bird spikes on signs, but those only work with smaller birds.
The warm winter also created issues because the ground didn’t freeze, so skunks were migrating to the airfield to hunt for grub worms. Skunks then attracted coyotes.

“When you remove one, that means there’s a hole for another one to come in,” he said.

Wyatt said TUL is continues to train operations staff on wildlife issues and the airport also contracts with Loomacres Wildlife Management, which provides training with staff.

“We’re always training, we’re always looking for new products,” he said.

“It’s like a cycle. First it’s the birds, then the mammals that come in,” he said.

KEEP THE COMMUNITY ENGAGED

John Weller, national wildlife biologist for the FAA, said there’s a big challenge with public perception in the management of wildlife at airports. People tend to focus on an incident where an animal is euthanized, so he said they need to do a good job of educating the community of this being a last resort.

“Airports are not parks. They are not nature preserves. They are airports,” he said.

Weller said it’s always good from a public relations perspective that everybody understands the wildlife management process.

“Literally, 95 percent of all wildlife management is quite boring because it’s all about habitat modification,” he said. “You want to make those airports and the lands around airports as boring as possible, as unattractive as possible.”

Weller said he has a four step process to wildlife mitigation he advises new biologists to focus on: modify the habitat to make it less attractive to wildlife; excluding animals using fencing; harass wildlife to scare them into leaving; and removal if they still remain on the property.

“Every animal is looking for food or water or cover,” he said. “And if they can’t find food, water or cover at that airport, they’re going to go elsewhere.”

Weller said birds are still the biggest problem with aircraft strikes, comprising of 97 percent of all strikes. The other three percent are comprised of other mammals, bats and reptiles. Exclusionary devices like bird netting in hangars or keeping them from perching on lights provide proactive management of birds. It also means reactive measures like harassment and removal doesn’t need to occur as often.

Airports also need to be cognizant of habitat modifications nearby and what it will mean for wildlife. FAA-trained biologists are looking for big attractants of bird habitat outside of the airport within 5 miles of the airport, so it’s important airport staff are liaising with the nearby community.

“I know that 71 percent of all strikes occur below 500 feet. I know that 84 percent of all strikes occur below 1,500 feet. I also know that when flights are coming in for a landing, all of these commercial airlines are coming in at about a 3 degree glideslope. That means at 5 miles out, they’re at 1,500 feet,” Weller said. “If we can work with land owners nearby but out of their jurisdiction to reduce some of those attractants, they can have a positive effect on 84 percent of those bird strikes.”

Weller said airports should be aware of major changes to the surrounding neighborhood to air concerns.

“Anytime there is a significant land use change, whether it be a landfill, large wetlands, large bodies of water, there is always going to be a public notification process,” he said. “That’s when the airport and the FAA get involved and if we can provide our input and say that we see you’re trying to modify this land use from this to something else and if it’s something we know will be a very strong attractant; we will do everything we can to work with them.”

Building strong relationships with the community can help address issues and build a working relationship with the community to keep on top of these potential issues.

“Nothing really beats boots on the ground. Many of these airports have a wildlife biologist who goes around and talks to the neighbors,” Weller said. “It may not result in changes to the land use, but it really sets the foundation for a good working relationship.”

KESTREL STUDY MAKES PROMISING OPPORTUNITY

The U.S. Department of Agriculture (USDA) has studied American kestrel population since 2015 to learn more about managing the birds at airports and determine if they will return to an airfield when translocated.

The study, “The evaluation of translocation as a management tool for American kestrels in an airport setting,” is being coordinated by the Wildlife Services National Wildlife Research Center and will conclude December 2020.

Brian Washburn, research wildlife biologist with the USDA APHIS Wildlife Services, said the agency has been looking at management of raptors and translocation of airports and recently was able to publish the first study related to red tail hawks and translocation.

Kestrels are of particular notice now, Washburn said, because there’s a nationwide decline in kestrel populations.

“There are a number of theories as to why they’re declining, but no one knows for sure,” he said. “But because they show up frequently at airports, we thought this was a good opportunity to look at this species in particular regarding how to best manage them through a non-lethal means.”

Washburn said the study is looking at effective ways to translocate the birds, what’s the minimum distance they need to take the birds and what are the return rates of the kestrels to an airport. Each bird in the study is given a unique color band and if they show up at an airport or involved in a bird strike, they can be reported.
It started out as a localized effort, but since went nationwide.

“All 50 of our state programs were invited to participate and currently most of our states are involved in it,” he said. “It provides us some opportunities to look at kestrels throughout their annual cycle. With an exception of a southeastern species, most kestrels will breed in the north an winter in the south.”

Samantha DiLorenzo, wildlife specialist for the USDA APHIS Wildlife Services, is stationed at University Park Airport (UNV) in State College, Pennsylvania, and was able to capture and relocate one of the birds to a park about 15 miles away.

Her bird did return and was involved with an aircraft strike, but the low return rate of the birds overall is promising.

“We’re all doing our best to give data to this study,” she said. “We’re all looking for other methods to manage wildlife at airports. It’s an ongoing thing. You’re always learning new things and finding new ways to make travel safer there.”

“Airports are great spots. We see these birds a lot more frequently because it’s basically a giant hunting ground for them,” she said. “It’s wide open space with lots of grass so they

Washburn said in all likelihood, kestrels are particularly drawn to airports due to food sources. The department did a study on this at Los Angeles International Airport (LAX) and discovered the big attractant of kestrels there was grasshoppers.

“We tried some management of the grasshoppers. It didn’t turn out to be particularly effective unfortunately, but it was our effort in addition to trying to move them away from the airport where it would be safer,” he said.

Based on preliminary data from the study, Washburn said they have discovered the kestrels have a return rate of about 5 percent when removed from the airport. In comparison, the study published in the Journal of Wildlife Management on red tail hawks showed the adult birds when removed from Chicago O’Hare International Airport (ORD) had a return rate of about 33 percent. Young birds had a higher rate of return in the spring and lower in the fall.

“Based on our preliminary data, based on the site specific studies, it seems the translocation method is a good tool to be used in the management of this species,” Washburn said. “We’re hoping from the study to learn some of the specifics of how to make it most cost effective so we know that we don’t have to take them 60 miles and we can get the same return rate at 30 miles.”