Dirty Jobs Abound in the Natural World

Dirty Jobs Abound in the Natural World

Most of us have had the displeasure of hurrying to our car, late for some appointment, climbing in, only to be assaulted by…sniff-sniff…the overpowering stench of doggy poo on a shoe. I can handle many of nature’s nasty smells pretty well but this one nearly gags me. Imagine if this stuff never went away and kept accumulating on the ground. For any of us that have even one big dog, this would be a problem. Heaven help the dog lovers out there with two or more large canines. Well, this article will be paying homage to the unsung heroes of the manure-removal squad, who could give Mike Rowe a run for his money any day. You guessed it, dung beetles.

Dung beetles are most assuredly not the only critters who make their living by what we would consider disgusting means. Carrion beetles, fly maggots, vultures and many other creatures would qualify for an episode of “Dirty Jobs in the Animal Kingdom.” However, the incredible beauty of many species of scarab beetles (the group to which dung beetles belong), resulted in high reverence in the ancient Egyptian culture. In more recent times, humans have realized the benefits provided by dung beetles and have intentionally introduced them in some places to manage dung accumulation in pasture systems. Their tunneling not only takes the dung below for a nutrient recycling function but also brings soil castings to the surface, which reduces soil compaction and improves aeration.

I have seen dung beetles many times, as they work in the yard to reduce my chances of “stepping in it.” Until recently, I have not paid close attention to the incredible beauty of our local species. I had a great opportunity the other day to observe several beetles as they reduced a pile of dog mess to smaller messes and pulled them into their tunnels for long-term storage. The showy, metallic colors of red and green made it apparent why some refer to these creatures as “rainbow” scarabs. They were happy to ignore my presence as I took pictures only inches away from their frenzied activity to salvage their prized doggy treats.

The dung serves as food for both young and adults during periods when they remain underground. Females lay a single egg on what is referred to as a “brood ball” of dung and there may be several of these pre-packaged meals with an egg in the tunnel system made by the beetles. I was able to get some good photos of a beetle as it worked above ground moving dung balls away from the mother lode. It appears to be a species known as Phanaeus igneus, which occurs in our area along with a similar species named Phanaeus vindex. In Florida, Phanaeus igneus tends to occur in sandy soils, while P. vindex prefers clay-type soils. The finely sculptured elytra (hard wing covers) of P. igneus also distinguish it from P. vindex. Eggs hatch into a grub that matures below ground before emerging as a mature adult to continue the cycle.

Dung beetle near burrow entrance

Females of this species are distinguished from males by the lack of a horn.

The dung beetle’s sense of smell is truly a wonder of nature. I have seen them flying in for a sniff test literally within minutes of deposition. Within the next day or two, the only evidence of your pooch’s crime will be small mounds of soil where the excavations took place. I was so taken with these little jewels of the manure pile that you might understand why I think you should be just as amazed. So, the next time you find a fresh pile in the yard, drop down to your knees for a closer look and be prepared to be amazed. If the manure-removal squad has not appeared on the scene yet, give them a few minutes. It won’t take very long. In the meantime, you can be thinking about how you will explain your behavior to your neighbors when they inquire.

Copy Cats Abound in the Insect World

Copy Cats Abound in the Insect World

image showing a wasp mimic that is actually a praying mantis

This praying mantis species mimics a wasp to avoid predation. Photo credit: Erik Lovestrand

When it landed on my hand, the first reaction was to brush it off as quickly as possible. However, something seemed to be slightly odd about this particular “wasp” that made me take another look. First, it was not prone to fly away as I moved my hand up for a better look. It even seemed okay with the interaction as I moved it around for a photo opportunity. There was also something odd about the shape of its body that wasn’t exactly wasp-like. As I looked closer, I realized that its head was very mantis-like and when it began grooming its antennae, I could make out the telltale folded arms that give the praying mantis its name. The yellow and black stripes encircling its abdomen, along with its wing shape and positioning veritably shouted “WASP!” I had never heard of a praying mantis that expertly mimicked a wasp so I did a quick internet search and found that this was a wasp mantidfly (neither a wasp nor a mantis). Mantidflies are grouped by scientists into a separate order called Neuroptera, which includes lacewings, antlions, owlflies, and others. Here are a few other mantidflies that mimic other wasp species.

A simple definition of mimicry would be: similarities between different species of animals.  It is different from camouflage, which refers to an animal resembling an inanimate object, but both are effective forms of deception that generally benefit an animal in some way. Another common insect that would fool most people is the soldier fly. It definitely looks like something that could sting but closer examination will reveal only one pair of wings (a fly trait) rather than two, as bees and wasps have.

Now, not to take you too far into the weeds on this subject, but we should also mention the different types of mimicry that scientists have identified in nature and note an example of each. Henry Walter Bates studied butterflies in the Amazon and described a type of mimicry where one species mimicked the look of another that had some particularly nasty defense to predation. The mimic was lacking the defense mechanism but benefited by predators avoiding it based on its basic appearance. This type of mimicry is now known as Batesian mimicry and a good example are the butterflies that mimic the monarch. Monarchs are toxic because of the milkweed they eat during their larval stage. After a predator eats a few it learns to avoid anything that looks similar, such as a viceroy or queen butterfly. Fritz Mueller was a German zoologist who described a form of mimicry, now called Muellerian mimicry, where multiple species mimic each other and they all have a similar defense mechanism. This spreads the benefit to all that look similar by reducing predation pressure on all.  The third type of mimicry is known as self mimicry, where an animal has one body part that mimics another (i.e. large eye spots to frighten or disorient an attacker), or a body part that may mimic some innocuous thing to fool prey into coming closer. We have a great example of this locally in the alligator snapping turtle. The tip of their tongue has a lure that resembles a worm and is capable of wiggling to enhance its effectiveness in tempting a fish to its doom in the vice-like jaws of the turtle.

Nature never ceases to amaze with the diversity and complexity of adaptations that various animals exhibit to gain an edge on the competition. When it comes to mimicry in the natural world, first impressions are generally wrong. I mean, that’s the point, right?

 

Buttonbush:  A Pollinator’s Favorite

Buttonbush: A Pollinator’s Favorite

Beginning in 2007 the US Senate, in support of the North American Pollinator Protection Campaign, declared the last week of June as “National Pollinator Week.”  As humans, we depend on pollen-moving animals for one out of every three bites of food.  Without birds, bees, bats, beetles, butterflies, and various other animals, many flowers would fail to reproduce.  In Florida there are numerous native plants that serve as hosts for these pollinators.

One of the favorites, due to its heavy flowering over the summer, is Buttonbush (Cephalanthus occidentalis).  It is a semi-aquatic woody shrub to small tree that develops white golf-ball-sized clusters of fragrant flowers, attracting various pollinating animals.  Bees of various species, several different wasps, assorted moths and butterflies, flies and even hummingbirds scramble for the flowers’ sweet treat within each of the trumpet shaped flowers. The pincushion-like flower balls stand on two inch stalks in clusters arising from stem tips and leaf axils.  They are produced over a long period in late spring and summer. The flowers give way to little reddish-brown nutlets which persist on the through the winter.  Buttonbush seeds are important wildlife food, especially for ducks; and the dense, impenetrable tickets provide nesting and escape cover for many wetland birds and herptiles.  Buttonbush is a fast-growing wetland plant that can be grown in a naturalized landscape if given supplemental water during dry spells.  It is at its best, through, in an area where the soil is frequently wet and can tolerate soggy soils.  Buttonbush is not drought or salt tolerant.  The deciduous shrub grows well in full sun to partial shade on soils that are acidic to slightly alkaline.  The leaves of Buttonbush turn yellow in the fall before dropping off.  While short-lived, requiring rejuvenation pruning to improve its longevity, Buttonbush (Cephalanthus occidentalis) serves a critical role to wildlife in the wetland habitat.  Deer browse the foliage and twigs.  Ducks, especially the mallard, eat the seeds.  And, the summer flowers attract bees, butterflies and moths; our wonderful pollinators.

Air Potato Leaf Beetles are Here to Help

Air Potato Leaf Beetles are Here to Help

Air Potato Leaf Beetle

I’m sure many of you could easily recognize air potato with its winding vines and heart-shaped leaves climbing high along roadsides, fencerows and natural vegetation, but could you recognize its key predator, the air potato leaf beetle? Believe it or not, a small, red leaf-feeding beetle was introduced and is here to help control the invasive air potato vine!

The Issue with Air Potato Vine

Air potato (Dioscorea bulbifera) is a plant species that is native to Asia and was first introduced to the United States as a landscape plant but has now become one of Florida’s most problematic invasive plants. Air potato has spread to 60 of the 67 counties in Florida, including many in the Panhandle. Air potato vines can grow up to 8 inches per day! The dense vines smother vegetation and displace native plants, trees and animals. The air potato vine is on the Florida Noxious Weed List. This means that is illegal to plant, propagate or move the air potato unless you have a permit.

The air potato vine spreads by vegetative reproduction. This is through the formation of aerial tubers, or bulbils that are formed in the leaf axils. The aerial tubers are roundish and vary in size. In addition to aerial tubers, air potato also produces underground tubers, making control that much more difficult. During the winter, the aerial tubers will drop to the ground and give rise to new vines in the spring.

Park managers and homeowners throughout Florida have battled with the air potato as its covered our landscape. For years, the primary means of control were by manually pulling, digging and destroying the tubers or by herbicide applications, until recently.

Classical Biological Control of the Air Potato Vine

Another method for controlling invasive plants is with classical biological control. This method involves searching for insects that feed exclusively on a plant in its native range and releasing them in an area that has been invaded by the plant. Scientists with the United States Department of Agriculture discovered the air potato leaf beetle (Lilioceris cheni) that feeds on air potato in its native range of Asia. After extensive testing, scientist found that the beetle is species-specific and poses no risk to other plant species.

In 2012, air potato leaf beetles were first released in Florida to help battle the air potato.  Now, according to the Florida Department of Agriculture and Consumer Services (FDACS), they are officially established in the state!  This means, they are here to stay and research has shown they are helping!

 

While you likely won’t see the beetles now, because they are overwintering (a period of suspended development), look for them in the spring! Adults are bright red with a black head and legs and about the size of your pinky fingernail. The females lay white, pale eggs on the underside of leaves. The egg-laying process causes the leaves to curl and cup. In addition to that, larvae feed on the leaves skeletonizing them. This feeding by the beetle negatively affects the growth and reproduction of the plant.

Skeletonized leaf damage to Air Potato from the Air Potato Leaf Beetle. Photo: Danielle Sprague

For more information on air potato leaf beetles, please visit:

Connecting With Youth Through the Love of the Outdoors

Connecting With Youth Through the Love of the Outdoors

Article by Rachel Mathes, Horticulture Program Assistant with UF/IFAS Extension Leon County.

Article by Rachel Mathes, Horticulture Program Assistant with UF/IFAS Extension Leon County.

By Rachel Mathes

My only brother and his family live in Appleton, Wisconsin. Though I’m only able to see my niece and nephews one or two times a year, we have a deep connection through our love of the outdoors.

Zach discovering the joy of nature. Photo by Rachel Mathes.

Zach discovering the joy of nature. Photo by Rachel Mathes.

Their middle son, Zachary, is a budding naturalist at just four years old. When I visit them, Zach, his brother Connor, sister Cecilia, and I, load up the wagon and go for walks on the edge of the prairie in their neighborhood. We start our walks looking for scat and signs of wildlife. Because the kids are so close to the ground, they often spot wildlife trails before I do. We talk about what animals may be there, what they eat, and how we can help them.

After each walk, we wind down at home with an iNaturalist session. Zach and his siblings help me choose what animal or plant we think we saw with the help of the app’s nearby suggestions tool. A favorite game we play after all our photos are entered into the app is a game we’ve coined, “where’s that animal?” We use the iNaturalist explore feature to find sightings of exciting creatures like wolves and beavers near their home. The kids have learned that even scientists often don’t see the animals they study, just signs of them.

At age three, Zach learned to identify milkweed with impressive accuracy. I pointed out the plant on a previous trip more than six months earlier and he remembered how to find them. Common milkweed, Asclepias syriaca, is a large leafed species that prefers winters a bit colder than we get here in the Florida Panhandle, but is native in northern states across the Eastern US, including Wisconsin. Zach is often stopping the wagon to scout for monarch caterpillars, finding even the smallest instars and eggs.

Zach learned to identify common milkweed, Asclepias syriaca, at the age of three. Photo by Rachel Mathes.

Zach learned to identify common milkweed, Asclepias syriaca, at the age of three. Photo by Rachel Mathes.

When I video call the kids from Florida, Zach is often asking to see my fruit trees, vines, and bushes. He knows that we have very different seasons than Wisconsin when I am eating blueberries in May and he’s still knocking frost off his snow boots. In July, he tells me about the raspberries they find in the woods with their dad. We both get a bit of seasonal berry jealousy. On my last trip we planted thornless blackberries in their garden together. It remains to be seen whether the birds will let the kids have a harvest, but the kids will be excited either way.

Though we may live a thousand miles apart, I know my relationship with my niece and nephews will continue to thrive as they explore the natural world around them. One day, I hope to introduce them to the awe of Florida manatees and alligators. Until then, I will relish the time we get to spend together outdoors in nature and on the phone together. I know that Zachary and his siblings will grow up having respect for the natural world and I hope he always exclaims, “Monarch! Look auntie Rachel, a monarch caterpillar!” on our walks together.

Author: Rachel Mathes, Horticulture Program Assistant with UF/IFAS Extension Leon County.

Wait, Wasps are Good Guys?

Wait, Wasps are Good Guys?

Yes, wasps are definitely good guys. Wasps are beneficial insects that feed on other insects, by destroying many harmful bugs that attack our landscape ornamentals and home vegetable gardens. However, they tend not to be very friendly to us, when we encroach on their territory. In other words, we really don’t want them to be close neighbors.

There are five members of the wasp family commonly encountered in Florida. These are hornets (Vespa spp.), yellow jackets (Vespula spp.), paper wasps (Polistes spp.), mud or dirt daubers (Sphecidae spp.), and cicada killers (Specius speciosus). Hornets, yellow jackets, and paper wasps are likely to sting if you go near or disrupt their nests. Mud daubers and cicada killers usually will not sting, unless you touch them.

Photo: Clockwise from top left: Hornet, Yellow Jacket, Paper Wasp, Mud Dauber and Cicada Killer.

Credit: P. G. Koehler and J. L. Castner, UF/IFAS Extension, Department of Entomology and Nematology.

There are parasitoid wasps, such as Tamarixia radiata, that are very beneficial, if you are a citrus grower. This native species is a biological control method for the Asian citrus psyllid, which is the vector for the devastating citrus greening disease. If you are interested in releasing juvenile Tamarixia radiata on your property please visit the Florida Department of Agriculture and Consumer Services website for an application: https://www.fdacs.gov/Divisions-Offices/Plant-Industry/Bureaus-and-Services/Methods-Development-Biological-Control/Biological-Control/Asian-Citrus-Psyllid-Biological-Control/Biological-Control-of-Asian-Citrus-Psyllid-in-Dooryard-Citrus-and-Ornamentals/Tamarixia-Release-Application or call 1-800-435-7352.

So, how do I identify nests? Hornets build football-shaped or pear-like nests usually in trees, away from populated areas, mostly found in the woods. Hornets and yellow jackets seldom live near people. Yellow Jackets build above ground nests, like those of hornets, but more commonly nest in the ground. Paper wasps are frequently found around homes where they construct their honeycomb nests in shrubbery and under eaves. Mud daubers often build their mud-cell nests on the walls and under the eaves of homes. Cicada killers, which are least troublesome of all, nest in the ground. Hornets, yellow jackets, and paper wasps are social insects. They live in colonies, like bees and ants. Mud daubers and cicada killers are solitary wasps.

If wasps do become a nuisance, you can eliminate hornet and yellow jacket nests by calling a certified exterminator of if you are an experienced do-it-yourself home owner, spray the nest opening with a potent wasp and hornet pressurized spray normally found at your local garden center or hardware store.  After treating any of the aboveground nests, leave immediately and wait until the wasps are dead. Then, return, knock down the nests, and burn it. To control mud dauber, scrape down their mud cells, and spray the area with an insecticide like pyrethrum or malathion to discourage re-nesting. To treat underground nests, spray with a pyrethrum or Sevin and seal the opening with soil, to keep the insects from escaping.

The severity of reaction to a wasp sting varies drastically, depending on an individual’s sensitivity to the venom.  At best, a sting will cause painful swelling.  In extreme cases, serious illness, or even death, may result.  If a sting victim has a history of hay fever, asthma, or other allergy or if allergic symptoms develop a physician should be contacted immediately

All types of wasp nest should be approached with caution. The best times to apply insecticides are in the early morning or late evening when most of the wasps are in the nest and least active.

For more information, contact your local county extension office.

Supporting information for this article supplied by retired UF/IFAS Extension Entomologist Dr. Don Short and other information can be found in the UF/IFAS Extension EDIS publication: https://edis.ifas.ufl.edu/pdffiles/IN/IN02100.pdf

For more information on Tamarixia radiata, please visit: https://www.fdacs.gov/Divisions-Offices/Plant-Industry/Bureaus-and-Services/Methods-Development-Biological-Control/Biological-Control/Asian-Citrus-Psyllid-Biological-Control/Biological-Control-of-Asian-Citrus-Psyllid-in-Dooryard-Citrus-and-Ornamentals

UF/IFAS Extension is an Equal Opportunity Institution.