The Secret Life of Evergreens

Figure 1: Lovely Evergreens

Figure 1: Lovely evergreens. Photo courtesy of www.treepicturesonline.com

Evergreen trees are in many of our living rooms this time of year. We have a lovely Fraser Fir in ours. They are also popular for landscaping since they stay green all year round.

Have you ever wondered why or how? It all has to do with the balance of energy. Many of these trees are found in cold climates and everything about them is adapted to handle tough conditions and take advantage of resources whenever they are available. I think this is the perfect time to explore those amazing adaptations.

So what exactly do I mean when I say evergreen? An evergreen tree is just what it sounds like. It’s a tree that keeps its green leaves all year instead of losing them like deciduous trees; maples, elms, cottonwoods. Most of our evergreens are conifers (Figure 1). This means that instead of having flowers and fruit, they produce cones. Even with cedar trees, the blue “berries” are actually a type of cone(Figure 2). Weird isn’t it? Often times, there are male trees and females trees. Early in the spring, have you noticed your car covered in yellow-green dust? That’s pollen floating on the wind; hoping to find a female cone. Once fertilized, a female cone may take several years, depending on the species, to mature. Why so long you ask? It’s hard to get all the energy needed to grow seeds in cold/seasonal climates.

Figure 2: Red Cedar female cones

Figure 2: Red Cedar female cones. Photo courtesy of www.arborilogical.com

Many of our evergreens have needle-like or scale-like leaves (Figure 3), and even though they keep their leaves year-round, that doesn’t mean they can grow year-round. Resources in the dead of winter might not allow for photosynthesis (the production of sugar from sunlight, water, and carbon dioxide (CO2)), but having leaves all year means they can photosynthesize whenever conditions are good. Very cold temperatures are not good for photosynthesis1, and even though northern trees are better adapted for this, winter temperatures can still drop below a functional level. Also, you may have noticed that winter days are shorter. They are even shorter the further north you go.

Figure 3: Different shapes of leaves for evergreen conifers.

Figure 3: Different shapes of leaves for evergreen conifers. Image courtesy of https://s-media-cache-ak0.pinimg.com

If there is no sun, there is no photosynthesis or growth. The needle leaves themselves have lower rates of photosynthesis but each leaf can live for several years on the tree. This is a way to balance the decreased availability of resources. Although they photosynthesize at a lower rate, evergreen trees do not have to expend energy making new leaves every year1.

Their leaves also help the tree cope with other tough conditions.  If you go over to an evergreen and feel the leaf, you will notice that it feels waxy, and you would be right. Evergreen leaves have a thick, waxy coating called a cuticle. This cuticle has pit-like holes in it to allow CO2 in but not let water out. That is very important in dry/cold environments. The cuticle and other tissues in the leaf also keep the water and cells inside the leaf from freezing so the leaf is not damaged even in the coldest of winter days (Figure 4)3.

Figure 4: Pine needles in ice.

Figure 4: Pine needles in ice. Photo courtesy of https://albinger.me

Another way needle leaves help evergreens is that the needle shape doesn’t hold onto snow as well. If you have ever had to shovel it, you know that snow can be very heavy. Imagine having all of that snow in your driveway sitting on top of you. The evergreen tree doesn’t want that either. Their leaves and down-sloping or flexible branches let snow slide off a lot of the time, or their branches are so flexible they bend under the weight instead of snapping (Figure 5).

Figure 5: Snow covered evergreens.

Figure 5: Snow covered evergreens. Notice how the branches bend. Photo courtesy of www.publicdomainpictures.net

The needles also have another defense, but this one protects against munching animals. Needles don’t taste very good and are hard to digest thanks to different oils and resins. Some animals have adapted to eating them, but overall, it’s a pretty good defense. Evergreens also have to battle fungus and insects too. If you’ve ever touched the trunk of a pine or cedar tree, you’ve probably gotten covered in pitch (Figure 6). This pitch is very sticky and also has anti-microbial properties that help the tree fight off fungal and insect invaders4.

Figure 6: Sap or resin running down a tree trunk.

Figure 6: Sap or resin running down a tree trunk. Photo courtesy of www.treeservicesmanchester.com

So whether you are gazing at the tree in your living room or one in the park, you can look at its branches and leaves and think how tough and resilient that tree is. Absolutely amazing! I’ll be bundled up trying to stay warm, and that tree is still growing and thriving like 15°F is no big deal.

  1. https://plants.usda.gov/plantguide/pdf/cs_juvi.pdf
  2. http://www.cgd.ucar.edu/tss/aboutus/staff/bonan/ecoclim/1sted/Chapter09.pdf
  3. http://www.psu.edu/dept/nkbiology/naturetrail/leaves.htm
  4. http://www.barkbeetles.org/spb/spbop/
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Fall Means Migrating Birds

Figure 1 Blackbirds

Figure 1: Blackbirds forms a flock as they migrate. Image courtesy of www.audubon.org

I apologize that I have not posted in the last couple months, but we are back in business. I hate to say it, but fall is here which means winter is just around the corner. The geese are gathering and flying together. Blackbirds are forming those flowing black clouds that are so cool to watch (Figure 1).

How do they do it? How do they know when to migrate and where to go?

First, let’s answer one big question. What is a migration? A migration is when animals from one location move in a seasonal pattern to another location. Migratory animals need to move to different location throughout the year to find the resources they need like food and breeding sites.

Figure 2: Map of bird migration pathways

Figure 2: Map of bird migration pathways across the U.S. Image courtesy of www.birdnature.com

Out of the more than 650 breeding bird species in North America, more than 50% of those are migratory. Some species only move short distances like changing elevation along a mountain according to the season. Others travel a little further across several states. However, some birds travel far into South America for winter1. It all depends on their needs and finding a place that meets them. (Please see the video below.) The Mississippi River alone acts as a corridor for over 40% of those migratory species. Bird watchers from around the country come to the Mississippi River to see the huge variety of birds that travel the flyway (Figure 2). So how do the birds know when and where to move?

This is a more difficult question to answer than you might think. There are entire fields of science that are dedicated to understanding the evolution and genetics of migration. How a bird knows it’s time to migrate depends on the species, and not all mechanisms are known or understood. More research needs to be done, but some migrations are triggered by a combination of day length, changes in temperature, and/or changes in food supply. Populations of the same species may migrate at different times1. For example, birds further north are going to start noticing changes in daylight and temperature sooner, and therefore begin their migration sooner than their cohorts that may be further south.

Figure 3: White Pelicans

Figure 3: White Pelicans and other waterfowl at a rest stop during migration. Photo courtesy of https://cindyknoke.com

Once a bird begins to migrate, it has to be able to navigate across thousands of miles and find places to rest and refuel throughout the trip (Figure 3). That’s no easy feat! Birds use a number of different cues and senses to navigate long distances. Click here to watch the journey of birds during their migration.

Birds can use information from the sun, stare positions, the earth magnetic field and landmarks along their journey1 (Figure 4). A bird’s eye and brain work together along with tiny bits of iron in the bird’s inner ear to determine which way points north.

Figure 4: Birds

Figure 4: Birds may use different methods of navigation. Image courtesy of www.smithsonianmag.com

This magnetic north can also be sensed by other nerves that help the bird determine the strength of magnetic fields which are stronger at the poles and weaker at the Equator. There is also evidence that the nerve connections between the bird’s beak and brain help it pinpoint its location2. Incredible! To learn more about bird migrations, I encourage you to watch the following videos:

On this journey, birds face a number of challenges. Imagine a little bird only 5 inches long weighing about as much as a pack of gum flying 5,000 miles from Minnesota across the Gulf of Mexico and down to Venezuela3. That’s what the Prothonotary Warbler (Figure 5) does every year! I struggle doing a 5K. This little bird puts me to shame. As this bird travels though it must be able to find sufficient food and shelter for the trip. It has to deal with dangerous weather and increased predation risk. Recently, migratory birds face a growing threat from an unlikely source, buildings and communication towers. Many birds are attracted to the lights and can become disoriented by the tower lights that may look like strange, new stars and disrupt their navigation. Millions are killed each year by collisions with structures like glass windows1. Read more on this problem.

Figure 5: Prothonotary Warbler

Figure 5: Prothonotary Warbler. Image courtesy of www.larkwire.com

Other threats to our migratory birds are deforestation, loss of wetlands and coastal zones, wind turbines, and house cats of all things. Migratory animals are particularly susceptible to habitat loss because they require multiple sites that can be far away and under various government entities. Songbirds’ homes may be protected in Illinois, but their winter site in the Amazon may not be or their stop-over sites might disappear. Thankfully, they do have some protection under the Migratory Bird Treaty Act. Read more about it.

If you would like to help migratory birds that may nest or move through your yard or town, there is plenty you can do to make a difference. You can join the American Bird Conservancy and/or become an Audubon Society member.  You can even set up your own celebration of World Migratory Bird Day Saturday, May 13, 2017. Learn how you can participate and spread the word and action to help migratory birds.

I hope you are as inspired by our fearless, feathered travelers as I am. If the Prothonotary Warbler can fly 10,000 miles a year, then we can surely do something to help them get where they are going!

Sources

  1. https://www.allaboutbirds.org/the-basics-how-why-and-where-of-bird-migration/
  2. http://nationalgeographic.org/media/how-do-birds-navigate/
  3. http://www.audubon.org/news/new-audubon-study-reveals-prothonotary-warbler-5000-mile-migration-path-first
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NGRREC’s Field Station Bursts with Backyard Biodiversity

Figure 1: NGRREC Field Station as seen from the river.

Figure 1: NGRREC Field Station as seen from the river. Photo by Louise Jett

Some of you readers may know that I work for Lewis and Clark Community College at the National Great Rivers Research and Education Center (NGRREC) in East Alton, Illinois (Figure 1). If you’ve been reading for a little while, it won’t surprise you to learn that I have been keeping a record of the wonderful species that I have found on the surrounding the Field Station. I thought that this would be a great subject for the month. If you haven’t come to visit NGRREC yet, there are a few things you should know about the property.

NGRREC was started in 2002 with the goal of becoming a leader in research and education related to large rivers, their floodplains and their watersheds. NGRREC is not a single entity, but the result of a partnership between the Illinois Natural History Survey, the University of Illinois at Urbana-Champaign and Lewis and Clark Community College in Godfrey, Illinois.

The property itself is pretty amazing, as you can see by the aerial views above. Our site, the Jerry F. Costello Confluence Field Station, was built in 2008 using green construction and is a great example of how renewable energy and recycling systems decrease the environmental impact of a building. In 2015, the building received LEED Gold Certification. That is incredible. To learn more about our building and organization, please visit www.ngrrec.org.

One of my favorite features of the property is the landscaping and plants. The space was designed for and planted with native plants and these host several different species of birds, mammals, amphibians, reptiles and insects. This is what I want to share with you today.

Figure 2: Male Indigo Bunting.

Figure 2: Male Indigo Bunting. Photo by Rob Curtis

Last summer, I stared wandering around the property on my lunch break, taking photos of interesting insects and birds, identifying and recording them. I’ve got a fairly long list so far, and it’s amazing for the size of the property. Let’s start by talking about the birds. In the last 18 months, I have positively identified 26 different species on the grounds including Gold Finches, Eastern Phoebe, Indigo Bunting (Figure 2), American Kestrel, Great Egret, Yellow Warbler, Brown Thrasher, Eastern Kingbirds (Figure 3) and Cooper’s Hawk. For many of these, I have seen potential nesting pairs or have seen their nests and fledglings.

Figure 3: Eastern Kingbird. Photo by Rick & Nora Bowers

Figure 3: Eastern Kingbird. Photo by Rick & Nora Bowers

I have seen some great snakes and frogs too. So far, I have seen four species of snakes; Black Rat (Figure 4), Blue Racer, Garter and Little Brown. I have also seen six species of frogs and toads; Green Frog, Bull Frog, Cricket Frog, Plain’s Leopard Frog, American Toad, and what I suspect is a Fowler’s Toad. There have also been some great mammals on the property including Mink, Red Fox, Coyote, Cottontail Rabbit, Deer Mouse, Woodchuck, Short-tailed Shrew and a vole of unknown species.

Figure 4: Black Rat Snake.

Figure 4: Black Rat Snake. Photo by Jennifer Hooks

The butterflies and bee diversity we have are amazing. All of native plants support a beautiful array of butterflies, moths and bees. Last summer, it seemed like every time I went out there was a new kind on some flower I hadn’t seen before. Sometimes, I would find the caterpillar and identify it using http://www.discoverlife.org/. This is a great website for caterpillars and butterflies. I also used http://www.illinoisbutterflies.com/damselflies.htm for butterflies, damselflies and dragonflies. Some of the ones I have found were Eastern Tailed Blue Butterfly, Pipevine Swallowtail Butterfly (Figure 5), Black Swallowtail Butterfly, Little Glassywing Skipper Butterfly, Azure Bluet Damselfly, Milkweed Tussock Moth, Monarch, Two-spotted Bumblebee (Figure 6) and Black and gold Bumblebee. These are just a sample of the cool insects that are found where I work. Finding these little treasures is much more fun than eating lunch inside.

Figure 5: Pipevine Swallowtail Butterfly.

Figure 5: Pipevine Swallowtail Butterfly. Photo by Greg Lasley

If you are looking for a place to see some beautiful wildflowers and wildlife, come see us. We are on the biking/walking trail that follows the river. Bring your family and walk up to our green roof on the south side of the building. Bring your binoculars and see how many different birds you can spot. Cameras are great to have to take pictures of the wonderful flowers that are blooming now and the lovely butterflies and bees that will be fluttering around them. We are located just down the road from the National Great Rivers Museum and adjacent to the Melvin Price Locks and Dam. Maybe I will see you there. I’ll be the lady rummaging through the grasses or standing in the trees looking for bugs and other cool critters. Hope you can join me.

Figure 6: Two-spotted Bumblebee.

Figure 6: Two-spotted Bumblebee. Photo by Andrew Block

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The Mysteries of Moths

Figure 1 Life cycle of a moth. Image courtesy of Taxo4254

Figure 1: Life cycle of a moth. Image courtesy of Taxo4254

I am sorry to everyone for the late post. Things at NGRREC are really picking up, and we are going into a very busy part of the year. From now on, we’ll only be posting one blog on the first Friday of every month. Now, to the subject of the week. MOTHS!

Butterflies are beautiful and brilliant, but moths are magnificent too. Moths can be equally as beautiful and have evolved incredible ways of avoiding hungry predators. Today, we are going to shed some moonlight on these incredible insects.

Moths, like butterflies, start life as eggs which hatch into caterpillars. They spin a cocoon and then metaphor into a beautiful moth (Figure 1). The instars you see in the diagram are different stages of the caterpillar’s development. Ever wonder how to tell a butterfly from a moth? That can sometimes be tricky. As scientists discover more butterflies and moths, the lines between the two become less obvious. Some ways to help decide are size, color, and wing shape. Most moth species, but not all, are nocturnal, and they tend to hold their wings in a way that hides their abdomen while butterflies do not1.

Promethea

Figure 2: Female Promethea Moth. Photo courtesy of Prairie Haven

Moths are usually smaller and less colorful, but there are definitely exceptions1. The Callosamia promethean or the Promethea Moth (Figure 2) is a large and wonderfully beautiful native moth that could be mistaken for a butterfly if it did not have the large, fuzzy body and fan-like antennae. This lovely moth’s caterpillars can be found on a variety of tree species; happily munching away on birch, wild cherry, lilac, tulip poplars, white ash, and others1,2. As with several other species, once this moth emerges as an adult, it does not eat. Males use their large antennae to smell out the females, and mating is the only goal for this moth during this life stage. Last summer, I gently scooped a female up off the sidewalk and put her back up into the tree. She fluttered to a couple different branches and then settled out of sight.

Figure 3 Hummingbird Moth.

Figure 3: Hummingbird Moth. Yes, that is a moth. Photo courtesy of the Virginia Living Museum

Moths are not only beautiful, but they are an essential part of our ecosystems. The caterpillars provide food for our native birds. Even species that eat seeds or fruits feed juicy caterpillars to their growing babies who need the protein. They also serve as pollinators for several plants. Not all moths stop eating as adults, and as they fly from flower to flower, they carry pollen and help the plants reproduce (Figure 3). There are many moths whose caterpillars only eat one kind of plant, and the adult also only feeds and pollinates that one plant. While they flutter about in the night, they might also end up feeding our local bats. Bats find moths with their echolocation, but some moths have evolved ways of avoiding detection or jamming their signals.

Figure 4 Luna moth. Notice the long tails that help keep it safe from bats. Photo courtesy of Richard F. Liotta.

Figure 4 Luna moth. Notice the long tails that help keep it safe from bats. Photo courtesy of Richard F. Liotta

One way moths make an escape is to fake out the bat with long flowing tails on their wings (Figure 4). These confuse the echo the bat hears, and they end up biting at the tails instead of moth’s body. Another cool evasion technique where moths fall out of the air to avoid being eaten is explained in the following video.

Bats are not a moth’s only predator. Spiders will also take a moth as dinner, but one moth in particular has had enough and calls the spider’s bluff. When confronted by a jumping spider, the metalmark moth flares its wings and extends its legs. In this position it looks an awful lot like another spider3, and it may even jump. In the following video, you can even see the spider raising its legs in a territorial defense posture; thinking it has to defend its space against another spider.

So moths are pretty darn cool. There is so much more I could say about them, but I’ve run out of space. If this has peaked your interest in the moths in your backyard, I encourage you to visit BAMONA (Butterflies and Moths of North America). You can learn what species are in your area, get region checklists for a mothing expedition, and report your findings.

If you would like to go mothing, visit www.mothnight.info for some great options for attracting them.

When you do find amazing moths, take a picture and identify it. Keep a list and report it to help promote moth conservation. For help identifying adults or caterpillars use www.discoverlife.org or  the BAMONA website. I hope you are as excited about these beauties as I am. Happy mothing! See you again June 3rd.

  1. https://www.loc.gov/rr/scitech/mysteries/butterflymoth.html
  2. http://www.butterfliesandmoths.org/species/Callosamia-promethea
  3. http://news.nationalgeographic.com/news/2007/02/070214-moths-mimic.html
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Getting the Low Down on Salamanders

Figure 1: Mudpuppy

Figure 1: Mudpuppy. Photo courtesy of Michael Graziano, mpgraziano@gmail.com

When you first see a salamander, you might mistake it for a lizard, but these guys are not reptiles. They are amphibians like frogs and toads. They have long bodies with very smooth skin, and species may have only 2 legs while others have all four. In the say way, the number of toes varies from none to four among species. Some have lungs and others have gills (Figure 1).

Some have neither but breathe through their skin. Incredible! In total there are about 600 species known to science1 and more are discovered all the time. The smallest species known is only 0.6 inches (Thorius arboreus) (Figure 2A) and the largest (Japanese Giant Salamander) can reach a whopping 6 feet and 140 pounds1 (Figure 2B). It may surprise you to learn that the Southern Appalachian Mountains have the greatest salamander diversity anywhere in the world2.

Figure 2: The smallest and largest salamanders in the world

Figure 2: The smallest and largest salamanders in the world. A) A pygmy salamander (Thorius arboreus) and B) the Japanese Giant Salamander. Photos courtesy of iNaturalist.org and journals.worldnomads.com

Just as salamander species have different body forms, they also eat different things based on their size and habitat. Some eat earthworms and invertebrates, and some eat snails, crustaceans, or fish; even other salamanders1. They also have varying breeding cycles and patterns. Some lay their eggs in water while others lay them on land. Some will spend their entire life on land, but lay eggs in water, and some will stay in the water all their life like the Hellbender (one of my favorites) (Figure 3).

Figure 3: Hellbender Salamander

Figure 3: Hellbender Salamander. Photo courtesy of George Grall, National Geographic

Some species hatch into miniature salamanders and bypass the larval stage, while others, like the Mudpuppy (Figure 1), never seem to totally lose larval features. Some species will lay eggs and leave, while others guard and care for their eggs3. If eggs are laid in the water, they will hatch into small larval babies that look like frog tadpoles with frilly gills (Figure 4).

Figure 3: Larval salamander

Figure 4: Larval salamander. Photo courtesy of Caudata.org.

Our native salamanders have great diversity. The Lesser Siren is one that you might not expect. It is strictly aquatic and has external gills and no back legs. (Figure 5A). The Hellbender is another aquatic species that can only be found in the U.S. and Asia and can reach 20 inches long (Figure 3). The Jefferson  salamander (Figure 5B)  and Silvery salamander (Figure 5C) are threatened, terrestrial species that spend most of their lives underground; only coming out to breed in ponds and wetlands. The Long-tailed salamander (Figure 5D) is a member of a family of salamanders (Plethodontidae) that are lungless and terrestrial. It can be found along swift, wooded streams or cave springs. Out of the 20 species found in Illinois, 6 are considered endangered or threatened4. Check out this resource to see the beautiful diversity of our native salamanders.

Figure 5

Figure 5: A) Lesser Siren. B) Jefferson Salamander. C) Silvery Salamander. D) Long-tailed Salamander. Photos courtesy of Tod Pierson, Virginia Herpetological Society, iNaturalist.org and Ohio University.

There are pretty interesting myths that have surrounded salamanders over the centuries. One of the most universal is the connection between salamanders and fire. They are often described as being born of fire or being fire starters. Salamanders were also once thought to consume fire, be rejuvenated by fire, or be elemental-fire itself. This myth is most likely attributed to salamanders’ tendencies to live in rotting logs. When these were put on fires, the salamanders would run out to escape the flames. Salamanders were often grouped with lizards into categories that included dragons and basilisks. In some folklore they were considered soulless creatures like giants and elves. Other stories claim they could poison water wells and fruit trees5.

These lovely critters are nowhere near the beasts of legend but are a diverse group and animals that face many threats in today’s world including habitat destruction, water pollution, pesticides, climate change, and the animal trade. If you find these little guys as fascinating and wonderful as I do and want to protect them, there are some simple steps you can take. For helpful tips, see how you can help.

If you find a salamander and want to know the species, leave it where you found it. Please do not remove it from the wild. Enjoy it in its natural home and do not handle it. Chemicals from bug spray, sunscreen, and lotions can be toxic and absorbed through their skin. Take a picture and head to the Discover Life website for identification assistance.

See you again May 6 for a conversation about wetlands and their role in your life.

References

  1. http://www.livescience.com/52627-salamanders.html
  2. http://highlandsbiological.org/nature-center/biodiversity-of-the-southern-appalachians/
  3. http://animals.sandiegozoo.org/animals/salamander-newt\
  4. https://www.dnr.illinois.gov/education/Pages/WASalamanders.aspx
  5. https://en.wikipedia.org/wiki/Salamanders_in_folklore_and_legend
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April Fools: The mimickers of the animal kingdom

Figure 1: Northern Mockingbird

Figure 1: Northern Mockingbird on a feeder. Notice the slate grey color and large white wing bands. Photo courtesy of Janet Furlong

Happy April Fools Day everyone! I’ve never been much of a pranker myself, but there are plenty of animal tricksters out there. Unlike us, they don’t try to trick others for fun. They do it for survival! Some animals mimic other, more dangerous animals to scare off predators. Others try to disappear into the background to either eat or avoid being eaten. Some even mimic others to attract a mate. I thought there was no better time to talk about the world of animal tricksters than today.

One of the iconic mimickers is the Northern Mockingbird (Mimus polyglottos). These birds are found throughout the U.S. and are often identified by their shape, color, and the white bands on their wings (Figure 1). If you have ever heard a string of different sounds or songs, you probably had a mockingbird in your yard. Mockingbirds learn different sounds in order to attract mates and defend territory. They continue learning songs, up to 200, throughout their life1 as you can hear in the video below. I encourage you to listen to the whole thing.

This bird’s variety is amazing. They will learn other sounds besides bird songs. I’ve heard of mockingbirds learning to mimic horses, car alarms, and cell phone rings. Now wouldn’t that be confusing? So the Mockingbird mimics for breeding purposes, but other animals mimic for defense.

The Gopher Snake (Pituophis catenifer), also known as a Bull Snake in some parts, is a large snake native to much of the U.S and into Canada and Mexico. When threatened, it mimicks a rattlesnake. It will hiss, puff up its body, coil, and flatten its head into a triangle-shape as you can see in the video below.

Although it looks very threatening and will bite if it feels threatened, it is not venomous3. That being said, it is never safe to approach or handle a wild snake if you do not know the species. If you come across a snake in the wild, please don’t kill it. Instead, walk slowly away and leave it alone. The gopher snake is a good guy; eating pests like mice and voles and is very important to our ecosystems.

Figure 2: Virginia Opossum

Figure 2: Virginia Opossum. Photo courtesy of Jillian M. Duquaine-Watson

Another defense mimicker is our continent’s only marsupial, the Virginia Opossum (Didelphia virginiana) (Figure 2). Opossums are like kangaroos in that they have pouches in which their babies grow. Once they are too big for the pouch, the babies will ride their mother’s back until they are big enough to keep up with her4. You’ve probably heard the term “playing possum.” That references this animal’s cool mimicking ability. It plays dead. Not only does it flop over and look dead, but it can lower its heart rate and exude a decay-like smell from its anal glands5. That is a good fooling.

Figure 3: Walkingstick Bug

Figure 3: Walkingstick Bug. Photo courtesy of Rosemary Bradley

Another way to avoid being eaten is to never be seen in the first place. Camouflage has led to some pretty incredible looking animals, especially in the insect world. Some of my favorites are the walkingstick bug and thorn treehoppers. I have great memories of finding walkingsticks in our family’s raspberry bushes. They get their namesake by their shape and resemblance to a stick or twig6 (Figure 3). The mimicry doesn’t end there. They move very slowly to avoid attention and will freeze and become stiff like a dead twig if they should be spotted7. There are 2,500 species of walking sticks, but only 4 are found in the Midwest. Most are found in the tropics6. Treehoppers are another well camouflaged insect. There are at least 3,200 species worldwide, and more are being discovered all the time. They come in a variety of shapes and colors with interesting thorax structures. Many have a triangular shape to them so they look like thorns when they are sitting still on a stem8 (Figure 4).

Figure 4: Two-marked treehoppper.

Figure 4: Two-marked treehoppper. Photo courtesy of www.bluejaybarrens.blogspot.com

So far, we’ve learned about animals using trickery to find mates and avoid predation, but some use it to find a meal. Crab spiders and praying mantises come to mind. Crab spiders are ambush predators and can change their color to avoid being seen by their insect prey9 (Figure 5).

Figure 5: Crab spider waiting in a flower

Figure 5: Crab spider waiting in a flower. Photo courtesy of Thomas Jordan

I have seen these little guys waiting inside flowers for unsuspecting flies or bees. The praying mantis is another ambush predator that is loved by many gardeners as a natural pest control. There are 20 species in North America, and they often rely of blending into the leaves to catch prey10 (Figure 6).

Figure 6: Praying Mantis

Figure 6: Praying Mantis. Can you find it? Photo courtesy of Nature08 coburn

Many different animals use mimicry and trickery to survive. These are just a few examples, but there are so many more. I hope you have enjoyed our Fools Day post. See you again April 15th. I have not decided on a subject yet, so it will be a surprise for us all.

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Recognizing Our Native Unstung Heroes

Figure 1: North American bees

Figure 1: North American bees. Figure courtesy of www.permies.com

When you hear the word “bee,” I bet you think of the fuzzy, honey-making honeybee. But did you know that we have many different native species of bees here in the Midwest and around the country? In fact, there are 4,000 different species of native bees1, and they are the most important pollinators for North America2.

These bees are responsible for pollinating 80% of the flowering trees, shrubs, and plants and are even responsible for pollinating 75% of the fruits and vegetables grown in our country1. So next time you are in the produce isle, say a little thank you to bees.

Figure 2: Four of the 4,000 North American native bees

Figure 2: Four of the 4,000 North American native bees. Images courtesy of www.popsci.com

Our native bees come in a variety of shapes, sizes, and colors (Figure 1 and 2). They also vary in the types of flowers they visit, the nests they make, and even the time of year they are active1. These differences are what makes all of these species able to survive through a little thing called niche partitioning. This is where different species have little to no overlap in how or when they utilize a resource. It reduces competition and allows for multiple species to coexist.

One example of this is the differences in tongue (proboscides) length. Some bees have long proboscides while other have shorter ones. The long ones are good for getting nectar out of deep flowers while the shorter ones are for more shallow flowers (Figure 3). Two species may feed at the same flower, but do it at different times of the day or year. Some bees are generalists and will visit a wide variety of flowers, but there are some bees that are specialized and may visit only a few types of flowers. A few are even more specialized and only visit one species of flower1. You can imagine then the outcome if either the flower or the bee was to go extinct. We lose not one species, but two.

Figure 3: Two different bee species.

Figure 3: Two different bee species. On the left a shallow flower, and on the right, a deep flower. Photos courtesy of www.fireflyforest.net and MSU

Nesting behaviors also vary among bee species. All bees take care of their babies, but they do it in different ways. Bumble bees form colonies and meticulously care for their offspring as a group, but most native bees are solitary and cannot care continuously for every baby. Some bees dig in the ground; creating mazes of tunnels ending in brood cells for baby bees (Figure 4). Other species have large jaws that can burrow into wood in order to make brood cells. Painting and staining or treating the wood usually deters them. There are other bees that will utilize holes left by other insects. However they make their nest, solitary bees will fill the brood cell with enough pollen and nectar to grow a single bee1.

Figure 4: Anthophora abrupta, the miner bee

Figure 4: Anthophora abrupta, the miner bee. Three females at their nests. Photo courtesy of Jason Graham and UF

Speaking of bumble bees, there are around 50 different species of them in North America (Figure 5). They are different from most of our other natives in that they are highly social and form colonies similar to honeybees with queens and worker bees. However, unlike honeybees, the old queen and the other bees die at the end of the summer. The new queen is left to overwinter and await spring to begin a new colony. If you would like to try your hand at identifying the bumbles in your back yard, check out www.beespotter.org.

Figure 5: Bumblebee species of Illinois and Missouri identification guide

Figure 5: Bumblebee species of Illinois and Missouri identification guide. How many are in your yard? Image courtesy of St. Louis Zoo

You can even participate in bee spotting. If you would like to learn to identify some common native bees or learn about how to distinguish bees and non-bees, see www.pollinator.org and www.beespotter.org.

Sometimes, insects that look like bees are not really bees. They are flies (Figure 6). The biggest give-away for a bee-mimicking fly is that they only have one pair of wings while real bees have two. But bee wings have hooks that lock the two sets together and making is appear like they only have one set1.

Figure 6 Bee-mimicking fly. Photo courtesy of www.edgevillebuzz.com

Figure 6 Bee-mimicking fly. Photo courtesy of www.edgevillebuzz.com

Sadly, our bees are in trouble. Disease, habitat loss, pesticides, and even competition with honey bees could be causes for the declines. If you would like to help bees, planting a pollinator garden is wonderful (Figure 6). Afraid of the stingers? Most native bees rarely sting, are incapable of stinging, or their sting is extremely mild. The best way to avoid being stung is when you see a bee, remain calm. Don’t swat at it or make a big fuss. If you leave it alone, it will leave you alone

If you are thinking about planting a garden to help our bees, read the following guides:

Remember to be careful about your pesticide use and make smart decisions when choosing where to get plants. Try to find natural or organic pest controls and purchase from organic greenhouses. Often times, pesticides can linger in the plant tissue and even be passed with the nectar and pollen. Check these sites for a greenhouse near you:

I hope this has peaked your interest in our native bees. They really are amazing, and they need out help. Happy Spring everyone!

Sources

  1. http://www.fs.usda.gov/Internet/FSE_DOCUMENTS/stelprdb5306468.pdf
  2. http://www.stlzoo.org/files/9613/3296/0636/uppermidwest-plants-for-bees-xerces.pdf
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