Denver is home to many urban wildlife species and has entire functioning ecosystems that support herbivores, omnivores, carnivores and scavengers alongside people and their pets, vehicles and buildings.
Everyone encounters wildlife in everyday city life, from watching a squirrel run along the fence and enjoying the sound of birds chirping, to "shooing" away raccoons scavenging through the trash. Because wildlife can sometimes seem like a nuisance, it's easy to take for granted the character they add to our backyards and parks. These creatures have adapted to our way of life, taking advantage of conveniences and habitats the city creates. Learn more about successfully coexisting with wildlife by reading below.
Avoiding conflicts with urban wildlife
Download full information sheet on avoiding conflicts with various wildlife species.(PDF, 320KB)
As the City of Denver continues to grow impacting wildlife habitat, it often times displaces and affects the natural order of wild animals. Some species continue to live in open-space areas, parks, undeveloped parcels of land, river bottoms, and on or near bodies of water. Others have adapted quite well to urban living; skunks, raccoons, squirrels, rabbits, foxes, coyotes and geese, in particular, seem to thrive in and near the city.
A little effort in preventing conflicts with wildlife goes a long way. The key to keeping unwanted wildlife out of homes and yards is to make them feel unwelcome:
- Do not feed wildlife! Even feeding songbirds may attract other unwanted animals to your property who are capable of finding plenty of natural food on their own
- Fence gardens and cover fruit trees with netting to protect your harvest
- Cover window wells with grates or covers
- Close holes around and under the foundation of your home so that animals will not be tempted to homestead. Bury wire mesh 1 to 2 feet deep in places where animals might gain access
- Don’t give animals the opportunity to get into your garbage. Store garbage in metal or plastic containers with tight-fitting lids and keep the containers in a garage or shed, only putting it out on your scheduled pickup day
- Keep pet food inside and cover up doggie doors at night
- Mark windows with strips of white tape if birds are flying in to windows
- Screen fireplace chimneys and furnace, attic and dryer vents. Keep dampers closed to avoid “drop-in” guests. Screen chimney tops from February to September to prevent birds and animals from nesting inside
- Seal all cracks and holes larger than one-quarter inch in diameter to keep out rats, mice, bats and snakes
Spring Wildlife Tips
As spring approaches, people will start to see newborn and young wildlife that appears to be sick, abandoned or injured. We frequently receive calls from concerned residents who want to help, but a hands-off approach is usually best. It’s natural to be concerned and want to help wildlife by picking it up or trying to feed it, but it’s important to understand that there is no substitute for their natural parents. There are very few instances where human intervention is necessary.
It’s common for adult animals to leave their young in safe places while they forage for food. Baby birds are often fledging or learning to fly near their nests when they are deemed abandoned by a human and picked up when they should be left alone.
What To Do
If you find wildlife that appears to be injured or abandoned, please take the following steps:
Reporting Wildlife Concerns
Use the following resources for wildlife emergencies:
Urban goose management is a complex issue that affects cities throughout the nation. Canada geese have been a part of Denver Parks and Golf Course landscape for many decades. The growing populations of resident Canada geese throughout North America and in the Denver Metro and Front Range area require ongoing management efforts using several strategies. Increases in the human population along the Front Range also contribute to human-goose conflicts such as accumulation of feces on turf and pavement; goose aggression during nesting season; over-grazing of landscape vegetation; and safety hazards for vehicles.
Learn more about DPR's Goose Management Program:
Since 2002, Denver Parks and Recreation (DPR) has implemented a Canada Goose Management Program that uses multiple strategies year-round to manage resident Canada goose populations. DPR actively manages goose populations in 15 parks through egg oiling, hazing, landscape alterations, repellents, scare tactics, and culling when necessary. The resident Canada goose population continues to increase in the Denver area by approximately 41% each year.
Strategies used in 2021
Egg Oiling: March – June 2021
- January: Permit acquired from USDA-Wildlife Services to oil Canada goose eggs
- February: DPR staﬀ trained on egg oiling process
- March: Egg oiling training offered to 2020 volunteers, with 4 of 10 trained
(due to COVID concerns, volunteers were not utilized for other projects)
- April: Nearby homeowners associations and businesses provided information about the egg oil program, asking for participation and permission to enter properties when necessary
- March–June: DPR successfully oiled approx. 2,012 eggs in parks throughout the city with help from Wildlife Services
Population Surveys: Year-Round
Surveys are used to monitor goose populations and evaluate management methods. DPR Natural Resources crews and USFWS performed goose population surveys in 15 Denver parks throughout 2021. Survey results show:
- The highest number of geese in Denver parks is between October and December, during the migration season
- Population estimates as of April 2021 (after the 2019-2020 culling; culling did not take place in 2021):
Sloan’s Lake: 68
City Park: 50
Garfield Park: 42
Washington Park: 31
Harvey Park: 26
Garland Park: 10
- Resident goose numbers are showing a slight increase
- Sloan’s Lake Park continues to have one of the largest populations surveyed
- As goose populations increase, management in urban landscapes also becomes more challenging
Goosinator Hazing: September – December 2021
- DPR Natural Resources and Park Operations continue to partner with Wildlife Services to haze geese in 15 parks
Coyote Decoy Pilot Project: September 2020 – March 2021
- This hazing method was not utilized after March 2021, though some park districts utilize the coyote silhouettes
- This system was not deployed in 2021 due to active ﬁelds
Goose Management in 2022
DPR will retain USDA-Wildlife Services to explore additional non-lethal methods for deterring geese. Through this collaboration, quantifiable objectives will be established for individual parks to reduce damage and conflicts with the public to acceptable levels using the integrated management approach. The Canada Goose Task Force continues to be involved and provide advice on DPR’s goose management efforts. DPR will continue to work toward management objectives:
- Decrease the Resident goose population
- Decrease people/goose conﬂicts
- Minimize damage to parkland
- Reduce disease outbreaks
- Improve water quality
Report prepared by Vicki Vargas-Madrid, Wildlife Program Administrator | January 2022
Denver Parks and Recreation (DPR) uses a multi-strategy approach for managing the goose population in Denver parks. This includes egg oiling in the spring, hazing in the fall and winter, the use of eco-friendly wildlife repellents, and most recently, culling. Additionally, work is being done to restore natural habitats along lake edges by planting native vegetation and creating visual barriers that discourage geese from nesting, while also improving water quality. It is not the desire or goal to eliminate all geese in an area. DPR’s Canada Goose management program strives to maintain a population or a reduction in goose numbers and related problems to a sustainable level that the park habitat can tolerate.
DPR consulted with U.S. Fish and Wildlife Service (USFWS), U.S.D.A.-Wildlife Services (USDA-WS) and Colorado Parks and Wildlife (CPW) federal and state agencies and engaged with various groups including the Parks and Recreation Advisory Board, neighborhood communities, wildlife advocacy organizations, the First Gentleman of Colorado, media and others to discuss DPR’s Goose Management Program. DPR remains committed to engage the public in various forums through education and outreach on wildlife issues.
The USDA-Wildlife Services final report of Denver Parks & Recreation 2020 goose management efforts will be provided in September. Although we do not have final data from this year’s culling efforts, preliminary numbers are indicating that our population management goals have been met, and culling will not be necessary in 2021. The multi-strategy approach will continue to be a part of DPR’s resident Canada goose management program as it has proven to be an effective strategy for the management of resident Canada goose populations in urban settings.
As part of DPR’s goose management efforts to continue its use of multiple strategies through community engagement, DPR will focus their efforts on the utilization of volunteers that assist with ongoing strategies for managing the resident Canada goose population in Denver Parks:
- Egg Oiling in the spring
- Hazing geese in the fall and winter months
- Creating and installing visual deterrents such as coyote silhouettes in various parks
- Conversion of traditional bluegrass turf to native vegetation where appropriate
- Potential research/goose banding project in 2021
- Utilizing dogs to haze geese in appropriate locations (City of Denver owned golf courses) – not a volunteer opportunity
USDA-WS addressed 4 of the 6 parks scheduled for management. After careful analysis of population data from each park, it was determined that two of the locations had a sustainable resident goose population and therefore, culling would not be necessary. Below are the preliminary 2020 resident goose population reduction efforts:
- Sloan’s Lake – 227 geese*
- Harvey Park – 55 geese*
- Garfield Lake – 125 geese*
- Garland Lake – 110 geese*
- Barnum Park – Did not need to cull as numbers are sustainable
- City Park Golf Course – Did not need to cull as numbers are sustainable
*A sustainable number of geese were left at each of these parks.
The geese were transported by USDA-WS to a licensed Colorado Department of Agriculture (CDA) processor inspected by CDA that must follow all state laws and requirements for euthanasia and processing. DPR’s contract agreement with USDA-WS states that the meat be utilized for consumption if it is deemed safe. The meat will be tested by random samples of each batch, separated by each park location. No meat will be donated before test results confirm the safety of the meat. USDA-WS will inform us of their findings. The process follows strict guidelines by CDA and the ethics of the American Veterinarian Medical Association (AVMA) for euthanasia of wild animals. Information regarding the process can be requested from USDA-WS.
Population reduction of wild animals is always a last resort in wildlife management. The intentional killing of healthy animals is recognized by AVMA, wildlife researchers and managers as an acceptable practice for the protection of public health, wild animal population control, biomedical research, and food production.
Supplemental Documents & Resources
The goal of beaver management guidelines within Denver park facilities is to support coexistence with beaver living in the city, minimize potential conflicts related to beaver and their activity, and support their role in our urban ecosystem.
These guidelines are based on research and best known management practices and includes a full spectrum of management tools. Basic principles that guide this and all Denver Parks and Recreation (DPR) Wildlife Management Plans are premised on the following principles:
- Urban wildlife is valued for biological diversity as members of natural ecosystems and providing educational opportunities and reminders of our larger global conservation issues.
- Urban wildlife and wildlife habitat are important to Denver residents. Although urban environments are more favorable to some species than others, coexistence is the foundation of wildlife management.
- Human safety is a priority in managing wildlife/human conflicts that pose a danger to people.
- Preventive practices including improving wildlife habitats, habitat manipulation, and responding appropriately during human and wildlife interactions are key to minimizing potential conflicts.
- Management techniques and decisions are based on a thorough understanding of the biology and ecology of the urban wildlife species.
- Education and communication play an integral role in supporting human and animal needs and coexistence.
Denver Parks & Recreation's beaver management strategy includes:
- Monitor and evaluate sites with beaver activity;
- Tree and vegetation management assessments; Determine if beaver can stay – If so, protect dens/lodges/habitat;
- Mitigate for beaver activity: (a) wrap/paint trees with 50/50 paint/sand mixture that are worth protecting (cottonwood, willow, ash, newly established landscaping trees, etc), (b) leave undesirable trees and vegetation for the beaver;
- Waterway mitigation – install Water Flow Control device (where appropriate) to prevent damming and allow water to flow;
- Relocation is not always the best option and will be assessed on a case by case basis, and always as a last resort.
Download more information about beavers(PDF, 97KB)
Living with foxes:
- Never feed foxes
- Do not leave pet food dishes out; always feed pets indoors.
- Keep garbage and compost in securely closed cans or inside
- Clean up fruit that’s fallen to the ground
- Clean under bird feeders and barbeque grills regularly
- Enclose chickens & rabbits in secure pens
- Use flood lights or motion activated lights
- Spend time in your yard. Human and pet activity will discourage foxes from entering
- Use ammonia soaked rags in trash cans or in areas where foxes have been visiting or trying to den
- Play a radio
- Keep fence well maintained so fox cannot slip underneath it
- Foxes can climb and jump 6 ft. fences; use other deterrents such as wire on top of fence may keep them from climbing over
- Trim vegetation high off ground to reduce cover
If a fox enters your yard, yell, wave your arms or a broom, or bang on something to make noise to scare it away. Be consistent, foxes are extremely intelligent and will learn locations where they are not welcome.
Danger from Foxes
Danger to small pets is possible, although typically rare. Pets under 10 lbs. would be most vulnerable to predation. Foxes typically avoid human contact and are easily scared. If a fox approaches, yelling and waving your arms should frighten it off.
When intentionally or accidentally fed, foxes can become aggressive. Remember that food means survival to wildlife and they will do what’s necessary to survive. It is not uncommon for playful foxes to initiate play with dogs or cats.
Behavior in Urban Environments
Foxes become more nocturnal in areas with a lot of people and are generally crepuscular, out in the early morning and evening, but can be out at any time of the day.
They are territorial and will maintain several dens throughout their territory with one larger den used for giving birth and raising kits. Dens are used every year and often passed on through generations.
Foxes generally avoid contact with people, but may initiate play with pets. They also have been known to “tease” dogs by barking and racing around outside of their reach. When a fox is fed, they can become too comfortable and bold around people and are more likely to bite or be injured by dogs, cars or people. To keep foxes safe and away from people and pets, it's best to chase them off and yell at them if approached.
Download the full fox information sheet(PDF, 137KB)
Prairie dogs are visually motivated and are likely to move into an area that looks like a good foraging site. By obstructing their view of your yard, they are less likely to move in. Prairie dogs are also naturally wary and avoid places where predators and other animals can hide.
Keep prairie dogs out of your yard with strategic landscaping:
- Create a visual barrier with a solid fence at least 3 feet high
- Build fences flush with the ground so they can’t peek through
- Add tall plants and shrubs on either side of the fence, as prairie dogs will see these potential hiding places for predators
- Plant hardy, low water-use native plants such as: rabbit brush, big sage, salt bush, fern bush, apache plume, and native switch grass
- Create a barrier underneath fence by digging down 12-24 inches to install a metal sheet or strong hardware cloth and cover with soil
Relocation of Prairie dogs
Relocation is a last option when damage is occurring to property.
In Colorado, it is lawful to capture, transport, and relocate black-tailed prairie dogs from one site to another only with permit from Colorado Parks and Wildlife (CPW). It's important that private property owners take responsibility to make educated decisions on how to manage prairie dogs on their property.
Please be aware of the following when considering relocation:
- Relocating any animal is a complicated process, and a professional should be hired or consulted before attempting to remove animals
- An approved relocation site with permission from the land owner is required
- County Commission approval is required if attempting to relocate from one county to another
Why don’t we remove all the prairie dogs from the city?
- Prairie dogs are important parts of the natural urban and prairie ecosystem, and other animals depend on them for food and shelter
- Removing animals without completely changing the habitat means new individuals will quickly move in and re-populate the area
- Prairie dogs have been identified as a species of special concern in Colorado because of the vital role they play in their habitats as a food source for animals such as fox, golden eagle and other birds and animals of prey
Download the full prairie dog information sheet(PDF, 266KB)
Fox squirrels are one of the most common squirrels found throughout the eastern United States, southern Canada and west through Colorado. They rely on trees to escape threats and live in forested areas and urban neighborhoods. Historically they were not in native prairies, but as we created urban forests we created great squirrel habitat. As mature forests are removed in other places, cities have become logical places for squirrels to go.
Behavior in an urban environment
Squirrels are successful breeders and populations can expand rapidly when there is ample food and shelter. They are playful, active and intelligent and can be bold in areas where they are fed by people. Feeding squirrels increases chances of aggression and bites and should be avoided. Squirrels in some areas have become so bold that they forage in backpacks and at picnic lunches!
Squirrels commonly make “leaf nests” for daytime and summer. Whereas, Birds will use mostly branches and feathers in their nests. Searching for warm, safe places in the winter can cause squirrels to move into attics, chimneys and crawl spaces. If there are small openings they can chew holes wide enough to enter.
We always recommend not feeding any wildlife. Bird feeders attract squirrels to your yard, and they can empty them frequently. No matter what techniques you try, accept that squirrels will get some bird food. If you choose to feed birds and don’t want squirrels in your yard, follow these guidelines:
- Use “squirrel proof” feeders, however, they are not foolproof
- Place a squirrel cone around feeder pole
- Make a separate squirrel feeder using suet, corn cobs, sunflower seeds or peanut butter. If there is an easier place to find food, they’ll make less effort towards the bird feeder
- Avoid hanging your bird feeder in or near trees; squirrels jump from extremely long distances
- Use a slippery post such as metal or PVC that is harder to climb than wood. Smear vegetable oil or Vaseline on pole
What to do if you find a baby squirrel
It is not uncommon for a baby to fall out of a nest. The mother will almost always retrieve her baby within two hours.
- Keep pets inside.
- Line a box with a t‐shirt type material and place it in a nearby tree high enough to keep it safe until mother comes
- If the squirrel has obvious injuries, place it in a dark, lined box in a safe, warm place. Contact a local wildlife rehabilitator
- If the mother does not come in 24 hours, contact a rehabilitator
- Baby squirrels are extremely fragile; keep them away from children, pets, and loud household noises. They can die from stress
- Do not attempt to feed the squirrel. Cow milk or human formula can kill it. A rehabilitator will have a formula specifically for young squirrels
Download the full squirrel information sheet(PDF, 601KB)
Coyotes are native to the Midwestern prairies and have always been found in Colorado's Front Range. They are highly intelligent, adaptable animals and are therefore one of the few species of that has been able to expand its range, even as natural areas and other species decline in numbers.
After decades of development, coyotes have become more urban as multiple generations of offspring have been born in cities. People, houses, pets, and cars are a normal part of their lives. An urban coyote has a completely different lifestyle than a coyote living in a rural area and has been raised by its family to survive in cities.
Feeding coyotes, either on purpose or accidentally, is the biggest culprit in creating problems. Coyotes in our urban environment have become used to living in close proximity to humans and associate people with food, reducing their natural wariness in interactions with people and pets. Every time a coyote sees a person and nothing happens, it increases their boldness and comfort in closer interactions.
Coyotes are naturally curious but timid and will normally run away if confronted, making attacks on humans are rare. In most cases, these attacks occur as a result of people feeding coyotes or habituating them in some manner. A coyote that associates humans with food may become demanding and aggressive. By feeding coyotes you put yourself, your neighborhood and the animals at risk. It is unlawful to feed or intentionally attract coyotes in most urban areas.
Make sure you can identify a coyote: they are brownish-gray with light gray to reddish cream-colored belly. Look for long legs, pointed nose and ears, and a bushy tail with black tip.
Discourage a coyote from approaching:
- Make yourself big and loud
- Wave your arms, clap your hands and throw objects (if available) at the coyote
- Shout with a loud and authoritative voice
- Do not run or turn your back on a coyote, face the coyote and back away slowly
- Teach children not to approach or feed any unknown animals
- Pick up small children if a coyote is nearby
While people are rarely in danger, coyotes can and do target pets as both competition and potential food sources. Human pets are often not adapted to protect themselves from wild animals and can be much easier targets than normal prey. Making educated coyote-management decisions regarding your pets is the best way to protect them.
Colorado Parks and Wildlife (CPW) has the final say on the lethal action regarding coyotes. It's been proven to be a short-term solution with long-term problems. When territory is vacated, coyotes are attracted to it, and coyote litters will increase in size to fill the territory (a single coyote can have up to 12 pups). Removing the pack leaders can lead to multiple packs forming with more females able to breed. There are often increases in the overall size of a local population, leading to increased fighting for territory and greater numbers of young animals causing problems for the community.
Relocating coyotes has been proven to be completely unsuccessful. They are notoriously difficult to trap and will travel huge distances to return to the area. Additionally, it is illegal in the state of Colorado to relocate urban coyotes.
Exclusion techniques --techniques to both remove attractants to coyotes and to discourage coyotes from entering unsuitable locations-- are currently the most successful tool in reducing coyote problems and populations in cities. It must be conducted on a community-wide level to see large improvements but even individual efforts can “teach” local coyotes which yards, parks, and people to avoid. Long term reduction in food sources for coyotes is the most effective means to reduce population size.
Hazing coyotes has proven to be the most effective method for instilling the healthy and natural fear of humans back into the coyotes. Coyotes are quick learners and consistent negative experiences can teach them to avoid people.
The Parks and Recreation Department/Natural Resources, in partnership with Colorado Parks and Wildlife encourage residents and city staff to use exclusion techniques on coyotes.
Exclusion techniques are not a quick fix. Relate this to never saying no to a child. The first time they hear it they won’t understand or believe it. Use the below techniques consistently over time as the most effective means to establishing appropriate human/coyote interactions:
- Individuals and groups of people responding and hazing whenever they see a coyote. Yelling, waving arms, acting aggressively, spraying with hoses, using noisemakers, vinegar water squirt guns will all make a coyote uncomfortable around people. Haze UNTIL THE ANIMAL LEAVES.
- Remove all human sources of food:
- Keep trash and compost inaccessible
- Pick up fallen fruit in yards
- Clean under bird feeders
Protecting your Family
- Never allow a coyote between you and a pet or child. A coyote will not want to get involved with a person
- Do not let cats run freely in neighborhoods
- Supervise small dogs and children when outside
- Keep all pets inside at night or in a completely enclosed kennel, as this is when coyotes are most active
- Maintain fences so coyotes cannot slip underneath. Add deterrents to the tops of fences that reduce a coyote’s ability to grab on and pull themselves up and over; coyote rollers and wire extensions can discourage animals attempting to breach fences
- Install motion activated lights in back yard. Keep lights on when dogs are outside
- Visually inspect yard before allowing any pet outside
Download the full Urban Coyote Information Sheet(PDF, 625KB)
Download the Urban Coyote FAQ(PDF, 433KB)
Learn about DPR's Coyote Volunteer Program(PDF, 121KB)
Benefits of Certifying Denver as a Community Wildlife Habitat
- Connect people with the natural world and support local biodiversity conservation
- Reduce environmental health risks associated with urban living, and facilitate wellbeing by improving physical, mental, and emotional health
- Promote pollinators, reduce stormwater runoff, and encourage water conservation
- Build equitable access to high-quality green spaces
- Complement and build on existing work being done to create and enhance green spaces
- Provide areas of wildlife connectivity throughout the city and beyond
What Will it Take?
Denver seeks to become the largest Community Wildlife Habitat in the West, hoping to join such large cities as Houston and Baltimore. In total, 116 other communities have been certified across the nation.
NWF’s Certified Wildlife Habitat program has been helping people take personal action on behalf of wildlife for more than 40 years. The program engages homeowners, businesses, schools, churches, parks and other institutions that want to make their communities wildlife-friendly.
The Community Wildlife Habitat project is part of NWF’s Garden for Wildlife program. Since 1973, NWF has provided millions of people with the basic guidelines for making their landscapes more wildlife-friendly. There are more than 200,000 certified habitats nationwide. For more information, please go to: www.nwf.org/garden. Learn more at NWF.org/Community and get more updates from the National Wildlife Federation at NWF.org/News.
City Nature Challenge | The Nature Conservancy
March 2019: Check out the spring newsletter from National Wildlife Federation with advice on native plant options for the season
CALLING ALL NATURE LOVERS: As Coloradoans, it’s only natural for us to love spending time outdoors, and April 27-May 3 more than 60 cities including Denver will compete to log the most observations of wildlife species and other natural elements. Denver Parks and Recreation’s 20,000 acres of urban parks and mountain parkland provides valuable habitat for a variety of wildlife and plant species.
During the last weekend of April, thousands of people from cities across the globe will get outside, look for nature, and log their findings in iNaturalist.org. You can help Denver WIN by participating in this challenge with us! Visit a nearby park with family and make this a fun family or group activity, and record your findings.
- April 27-30: Take a picture of something you find and note the location. Your finding can be any kind of plant, animal, fungi, slime/mold, or any other evidence of life such as scat, fur, tracks, shells or carcasses.
- May 1-3: Share your observations by uploading your findings at iNaturalist.org. (more information on website)
Results of the challenge will be announced on Friday May 4th by The Nature Conservancy!
About the Nature Conservancy
The Nature Conservancy is a global conservation organization dedicated to conserving the lands and waters on which all life depends. Guided by science, we create innovative, on-the-ground solutions to our world's toughest challenges so that nature and people can thrive together. We are tackling climate change, conserving lands, waters and oceans at an unprecedented scale, providing food and water sustainably and helping make cities more sustainable. Working in 72 countries, we use a collaborative approach that engages local communities, governments, the private sector, and other partners. To learn more, visit www.nature.org or follow @nature_press on Twitter.