Landfill operators know them all too well: quite possibly the most frequent visitors to their sites, birds can be squawky, ravenous mess-makers that often overstay their welcome.
The various types of birds that post up at landfills, whether seagulls or falcons, can present a nuisance to employees and the surrounding community alike.
And while a growth in population of these species’ more iconic cousin, the bald eagle, is celebratory news to many, the population boom is creating issues both within and outside landfill boundaries for many sites throughout the country.
The Cedar Hills Regional Landfill in Seattle is one such site, and the mix of bird populations in the area has required innovative solutions for warding them off.
“We’re dealing with eagles and starlings and ravens and gulls. There are many species we’re managing, so the approaches can vary,” says Pat McLaughlin, the director of the King County Solid Waste Division, which oversees the landfill. “You try to be as proactive as you can, but then as they change their habits, you have to adapt your strategies.”
Know your birds
Though bald eagles are not the primary bird visitors most landfills see, their recent population boom that officially took them off the federal list of threatened and endangered species in 2007 has required new bird diversion strategies. As one of the largest birds in the country, they don’t always respond to the traditional scare tactics that work on small species. To make things more complicated, they’re protected under the federal Bald and Golden Eagle Protection Act from being harmed, trapped or disturbed in any way.
Whether it’s an aggressive eagle population or another species that occupies a site, the first step for operators looking to ward off any bird population is knowing what they’re dealing with.
“Your strategy always depends on the dominant infestation at any given site,” says Michael Gallion, the head of business development of Carson, California-based Bird Barrier, which provides bird diversion products and strategies for a range of sites.
Different types of birds respond to different solutions, so identifying the primary visitor narrows down diversion options. For example, products like bird spikes are effective in keeping pigeons from roosting on roofs, but larger birds can pluck the spikes right off.
Doing research on a site’s primary visitor, including into their feeding behaviors, preferred resting places and responses to disturbances, can go a long way.
McLaughlin says his team has worked with a number of biologists, consultants and organizations to help devise a plan of action. For sites looking for assistance, companies such as Bird Barrier also offer consultation and planning services.
“We really try to partner with many agencies and professionals to understand best practices, be on the leading edge and also make sure that while we’re trying to mitigate the risks of site impact, we’re respecting the wildlife in the process,” McLaughlin says.
Whether dealing with eagles, smaller birds or a mix, the primary diversion technique remains: identify their main motive for visiting the landfill and remove their access to it. This is especially important to do before the birds nest in the area, if possible, since nesting equates to a more permanent presence in the vicinity.
A 2015 study of bald eagle behavior near landfills in the Chesapeake Bay region of the U.S., for example, found that juvenile eagles were the most likely age group to seek food from landfills, while most others were just looking for a place to rest.
That’s why resting places are one of the primary elimination targets for McLaughlin and his team at the Cedar Hills landfill as they work to prevent eagles from getting comfortable there in the first place.
“We have some retaining walls that birds like to nest in, so we’re filling in those gaps that may otherwise provide a dark nook and cranny for them to rest in,” McLaughlin says. “It’s also important to make sure that there aren’t ample food and water sources either, so no shelter, no food and no water.”
Normal landfill maintenance, such as keeping grass short and covering waste daily, can also be effective in discouraging bird populations from taking up residence in a landfill.
“Simple things like putting lids on trash cans or keeping dumpsters closed can have a huge impact,” Gallion says. “If they know dumpsters are left open, they will habituate to that situation.”
Target their senses
While removing basic resources is a useful tactic, it’s often not enough to completely eradicate bird issues, especially if they have nested in the area.
These birds are considered “residents,” Gallion says, and are much more difficult to uproot. The goal is to get them to relocate, which often takes care of the issue long-term or even permanently.
“In general, your strategy in bird control is always to relocate resident birds. Trash creates an environment that attracts the birds, and eventually the birds will pick up residence because it’s proven to be such a viable resource to live off,” Gallion says. “Typically, when they relocate, they don’t ever come back.”
A variety of products exist to fend birds off the site for good, from distressed bird call noise deterrents and mild shock systems to undesirably scented products and light reflectors. These solutions target birds’ various senses and trick them into believing a threat exists in the area.
Optical gel, for example, is a product that tricks birds into thinking a fire is in the area by reflecting UV lighting, creating the illusion of flames for birds, Gallion says.
These techniques need to be employed in a combinational approach for maximum efficacy. Birds are bold, and when they encounter a threat continuously, they often venture to examine it further. If they rule out a threat, they begin to ignore it and return to the site.
Even optical gel, which also has scent and tactile deterrents for when birds get close enough to touch it, should be used alongside other systems and techniques to confuse the birds long enough for them to decide to leave. “It’s almost like an antibody. If you use the same antibiotic over and over, the body gains immunity to it,” Gallion says.
Techniques should be introduced strategically on a rotating basis. The best strategies use techniques that comprehensively cover all areas of the landfill, including the perimeter and any office spaces where the birds can nest.
“In terms of waste and recycling customers in these big, wide-open spaces, a very specific strategy initiative has to be involved,” Gallion says.
Thinking outside the box
Over in Seattle, McLaughlin has tried a few products created specifically to deter birds. One was a drone disguised as a hawk, which had varying success depending on the bird.
For the eagles, it didn’t go over well.
“The eagles were not a fan of the drone and took it right out of the sky,” McLaughlin says.
Instead, officials there have had success with trapping and relocating smaller birds, and with bottle rocket-type pyrotechnics for dispersing larger groups of birds. One of their most successful deterrent techniques is one of the most traditional, albeit with a unique twist.
McLaughlin says the crew dresses up a scarecrow in a bright vest and hard hat to look like the staff member who deploys the other bird diversion techniques, tricking the birds into thinking he’s constantly present.
“For us, it’s been taking a combination approach, but also constantly being aware of what’s working and what’s not,” McLaughlin says. “All these things help, but we haven’t found a silver bullet or a one-shot homerun approach.”
While the biggest problem with birds is often the nuisance, they can also be a health hazard to landfill crews if they carry disease. Ingesting waste can cause the birds harm as well, which presents its own issues. And in some cases, bird problems can filter out into the surrounding community. Residents near the Cedar Hills Regional Landfill have complained of finding waste scattered across their yards and blame the eagles at the landfill for the mess, according to the Seattle Times.
“It’s not so much an operational challenge with our ability to manage waste. It’s an operational challenge for us to try to manage the birds,” McLaughlin says about the nearly 200 eagles that occupy the landfill in peak season.
The King County Solid Waste Division is currently in the process of developing a bird management plan to track the types of bird visitors at the landfill and develop mitigation solutions for each one. McLaughlin says they’re doing so not only with the help of the organizations they’ve consulted with in the past, but also with a wildlife biologist they plan to hire and keep on staff.
“Some of these animals are very smart,” McLaughlin says. “You have to evolve your approach. It’s standard for a period of time, and then the standard needs to keep changing to make it effective.”