Roadkill Cafe and Its Guests

Tongue-in-cheek books and articles notwithstanding, there is not a one of us who has not seen the unfortunate sight of animals laying dead along the sides of highways, the losers in a head to head battle with cars and trucks. Millions of animals, domestic or wildlife, are killed in this manner each year in the United States……but that’s not what this article is about. What should be recognized is that the death of any animal sets off a chain reaction of recycling, as Nature attempts to put all that nutrition and substance back to use now that the original owner, the now-deceased animal, no longer is using it. Who cares? Well, certainly the animal now providing a meal to hundreds or thousands of other critters, but possibly also the homeowner, who sees some unwanted, wriggling worms falling out of their ceiling in their home. And, as many people now know from some new and popular TV shows, the presence of bugs in bodies also is a valuable tool in crime scene investigations.

In tropical rain forests there is often a lack of available nutrition for plants and animals to feed on. Therefore, when something dies – whether a plant or an animal – there is an immediate feeding frenzy and a heated competition to be the organism that takes advantage of this available food. Organic material is recycled very quickly in tropical jungles, and you don’t see things laying around on the ground for very long. In our more temperate, drier climates in the U.S. this recycling takes place quite a bit more slowly, but it is accomplished nonetheless, and often may begin just as quickly as it does in the humid jungles. In fact, it has been shown that within just a few seconds after death an animal’s body begins to emit different odors that are highly attractive to the first wave of insect recyclers, as tissues in the respiratory tract begin rapidly to decompose. These first visitors will be blow flies, and for the next couple of weeks there may be a large population of maggots feeding on the carcass.

This is one of the first messages I hope to pass along here. It is very common for an animal to die in an attic or a wall void of your home. Perhaps you knew you had rats, as you heard the sounds of their activity over the ceiling of your bedroom at night, and bought some rodent bait at the local store to eliminate the problem. The instinct is to just fling the bait packets or wax blocks to various corners of the attic in the hopes that the offending rat will find them more easily, but the problem occurs when that rodent dies and you are unable or unwilling to remove the body. This is one reason that rodent control in your home might best be done with traps, placed where you can easily check them each day and remove them once the rodent is captured. Not only will a decomposing body of any animal larger than a good sized mouse begin to give off terribly offensive odors, but within just a very short time that body also will have attracted flies, and the flies lay their eggs, and the eggs become maggots.

Now, the habit of the larva of a blow fly, which is those big, buzzing, shiny blue or green flies, is to develop fully within about 7 to 10 days, and the next step for that maggot is to become the pupa. Rather than transform to that immobile pupa stage right there in the carcass, where it likely would become a meal for its brothers and sisters, the fully grown maggot leaves and begins wriggling away. It is looking for a protected crevice that it can get into, and there it will pupate. As the maggots wriggle across the attic they often fall through openings in the ceiling below, perhaps light fixtures or vent openings, and land on the floors and counters in the living area below. If this is the kitchen counter, and a meal is being prepared, it’s a safe bet that the homeowner is not going to welcome wriggling maggots on the counters. What is the solution? Obviously, someone needs to go into the attic and remove whatever it is that is providing bed and breakfast for these critters, and vacuum up as many of the wandering larvae as possibly can be found.

Another very common source of these large maggots in and near homes will be decomposing garbage. One of the reasons that we have weekly garbage service in our country is so that our waste can be removed in a time period less than it normally takes flies to complete their life cycle. We throw a lot of organic material into our trash cans – meat byproducts, vegetable trimmings, leftover foods that are no longer wanted – and we keep a lid on the can (hopefully). The lids are not always tight-fitting, and because it’s enclosed a nice humid and warm environment exists that speeds up the decomposition process and the breeding of the flies. Clean waste receptacles will greatly reduce the flies around your home.

Just to complete this thought on reducing fly problems around your home, realize that most of our “filth flies” are not too picky about what kind of rotting organic material their larvae feed on. Whether it is plant or animal matter, as long as it is nutritious and decomposing it becomes fly food. If you have pets that use the yard for a bathroom their droppings can be a huge source of fly production, and should be cleaned up at least once each week. Lawn clippings often get tossed into piles, and shortly will begin to rot within the pile and produce the perfect conditions for maggots to live and grow. Improperly maintained compost piles also may offer sections of rotting materials. If you are in an area of the country where garden snails are abundant, and you kill off large numbers of them with snail bait, even these small corpses will produce great numbers of flies. Cleanup and good yard maintenance are important concepts in fly control.

The second wave of insects to feed on a dead animal, once the flies have done what they can with it, may be carpet beetles. We often think of carpet beetles only as those darned bugs that eat holes in our clothing, generally fabrics made from wool or other animal fibers. It’s very hard to feel sympathy for the carpet beetles, which are only doing what nature intended as they recycle dead animal materials, when they are destroying a favorite sweater or jacket. But, hair is hair, and even though we may have done something fancy with it, by dying it and turning it into a fabric, Mother Nature is still determined to return all of that nutrition back to the soil. To termites your house is just one big dead tree, and to carpet beetles your wool clothing is just dead animal hair. By removing dead animals from your attic, if you perform your own rodent control, you may prevent the introduction of a great many carpet beetles to your home, and help keep other things protected as well.

One of the final bugs to feed on an animal carcass will be another group of beetles called Hide Beetles. They are related to the carpet beetles, but instead of eating the hair or feathers (if it’s a bird, of course) the hide beetles feed on the last bits of flesh and skin. They are so effective at their role that museums will even employ squads of hide beetles to help them clean off the bones of animals when they want a clean skeleton for their museum display.

This road kill café took an interesting turn a number of years ago, and it has become an extremely important science in crime scene investigations. The knowledge of just what kinds of insects will be found in a dead animal, in a particular situation, and how long they and their life stages will be there, is of tremendous help to law enforcement in determining many facts about a crime such as a murder. When a human body is discovered an immediate gathering of evidence takes place, including collecting and preserving any insects found on that body. If maggots are present it can be very accurately determined how long that body must have lain at that place, based on the kinds of flies represented and how long it would have taken for the larvae to grow to the stage found there. This knowledge helps to pinpoint the time of death and other factors involving the crime, and can be of importance in solving the crime and implicating the person responsible for it. This science is referred to as Forensic Entomology.

So, the presence of insects feeding on and within the carcass of a dead animal is a natural and necessary part of a healthy environment, and without their activities we likely would have a much messier environment around us. We may not want these recyclers in our home, so we take the appropriate steps to keep their food supply from becoming available. We already have mentioned the proper method of doing rodent control within the structure, using traps that capture the offending animal rather than poisons that may allow it to wander off to inaccessible places before it passes away. There are some other steps that you should consider as well, for keeping other kinds of wildlife out of the structure, such as birds, raccoons, squirrels, or bats. This involves “exclusion”, meaning you closely inspect the outside of the home and determine all those places where these critters could squeeze into a wall, attic, or crawl space. You then permanently close those openings so that you never have to deal with the consequences.

Important inspection points include:

  • Screens on vents to the attic or crawl space – ensure these are in place and not damaged
  • Crawl space access doors – usually are found on the outside of the home, and either do not fit well or are opened and left ajar. It takes only a one-half inch gap to allow a rat to squeeze through.
  • Pet doors – particularly those left available at night will admit the curious wildlife that then can access other areas of the home.
  • Gaps under exterior doors – exterior doors leading into garages are notoriously poorly fitted. Brush strips can be installed to close off this animal highway.
  • Rooflines and eaves – often are poorly constructed using low quality wood, and holes and gaps exist that bats easily can squeeze through.
  • Holes in outside walls that admit pipes or cables – particularly if the work was done after the home was completed, these holes may get crudely punched through the stucco or siding and left with large gaps. These can be filled with caulking, mortar, or other materials.

By closing your home to the entry of animals you keep out more than just the wildlife. A great many insect pests also find these openings convenient. Properly sealing gaps around windows and doors also will go a long way in keeping the indoor environment where you want it, with less heat escaping in the winter or entering in the summer. We can recognize the benefit of having animals such as bats in our environment, as they feed on great numbers of night-flying bugs. However, it is an undeniable truth that when they take up residence within our structures they produce conditions that are not healthy for us. Their feces and urine will begin to accumulate within their harborage sites, and these waste materials are well known for containing many kinds of disease pathogens that can affect our health. The same can be said for bird and rodent droppings.

So, as you can see, we started off this short article on a pretty gruesome note, but tried to work it into being helpful to you. There is just something about “BUGS!” that makes the skin crawl on most people, but they are amazingly interesting animals. They are involved in nearly every aspect of our natural environments, and even when their activities are harmful to us, our property, our health, or our happiness, it may be useful to focus on the overall picture and the reason that bug is doing what it does……as long as it does it somewhere else.