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April 19, 2021 By crm

Lacewings: Beauties & Beastly Babies

By Judy Ferris, ACLT Guest Blogger

Lacewings are an insect we may have heard of but perhaps never seen. Adult Lacewings get their names from the delicate network of ‘veins‘ which characterize their wings.

Unfortunately, we see Lacewing adults only rarely because they are nocturnal. Yet, adult Lacewings are the miniature fairy princesses of the crepuscular world. Measuring about ¾ of an inch long, they have bright green bodies and golden eyes. Gowned in lacy, diaphanous wings which almost glow, they flutter in the darkness on a nightly quest for nectar, pollen, and honeydew.

Hungry bats also roam the darkness, using their sonar to detect delicate fairy princesses in flight. Amazingly, Lacewings have specialized veins in their wings that sense the ultrasonic sounds made by hunting bats. Alerted to danger, a flying Lacewing takes evasive action. It closes its wings, making a smaller sonar image, and sinks to the ground out of danger.

During her lifetime, which may last 4-6 weeks, a female Lacewing lays up to 200 eggs. They are placed on the undersides of leaves, preferably near a burgeoning colony of aphids or other soft, yummy pests.

Each egg is cleverly placed at the end of a slender stalk which is coated with ant repellent. The stalks may also prevent newly hatched lacewing larvae from eating their unhatched siblings!

While adult lacewings are gentle and fairy-like, Lacewing larvae are the exact opposite! Known as Aphid Lions due to their voracious feeding habits, Lacewing larvae are shaped rather like alligators.

The feisty babies are about ½” long. Note the no-nonsense feeding apparatus on the head. The large, curving mouth parts (known as maxillae) have hollow grooves which serve as fluid conduits. Although Aphid Lions have eyes, their senses are very weak. Instead of spotting prey visually, they swing their upper bodies back and forth like a rampaging Attila the Hun, until they crash into something edible. Grasping the unsuspecting victim with their maxillae, they inject potent toxins into its body. So powerful are these chemicals, that they can dissolve the insides of an aphid in 90 seconds! Let the feasting begin! Body fluids from the aphid are sucked out via the maxillae. As the withered husk of the aphid runs out of fluid, let there be no doubt, they are good to the last drop! The Aphid Lion, with prey gripped in its curving ‘jaws‘, tilts its head back and shakes the carcass to savor every ounce of sugary goodness.

But wait! There‘s more to this story! An Aphid Lion, alone and unprotected, is a juicy target for insect or bird predators. Thus, as soon as they leave the egg, some Lacewing larvae begin collecting items to form a shield‘ on their backs. This protective cover may consist of spent egg cases, the shed skins of molting larva, or the withered bodies of the Aphid Lion‘s victims. Over time a significant pile of detritus accumulates atop the larva; the perfect camouflage for a tiny, but fearsome predator.

Once the larvae matures, it spins a cocoon; incorporating a shield of dead insects and other debris. Here in Maryland, Lacewings overwinter in these cozy cocoons; surrounded by molted body parts of relatives and the empty husks of victims. In spring, a fully formed-adult Lacewing with translucent wings emerges. A beastly baby no more!

For a fascinating peek into the lives of adult Lacewings and Aphid Lions in action, be sure to check out the short video below.

Aphid Lions typically eat about 200 aphids or other pests per week during their 2-3 week developmental cycle. In addition to aphids, the larvae also eat mites, insect eggs, and fearlessly wade in to attack much larger prey such as caterpillars as well. They are valuable additions to any garden and are even used for large-scale pest control of some crops. Lacewing eggs, larvae, and adults are all available for purchase online for use as biological pest control. Gardeners can attract Lacewings by using certain plants and tolerating beneficial weeds; Asters, Cosmos, Sunflowers, Dill, and Dandelions.

My magnifying glass is at the ready as I almost look forward to discovering aphids in my garden this spring. Can‘t wait to see what sort of insect mayhem transpires!

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April 16, 2021 By crm

By: Nicole Stevens, Chesapeake Conservation Corps Member

A long-drawn-out and tolling cry,
That drifts above the chorus
Of shriller voices from the marsh
That April nights send o’er us;
A tender monotone of song
With vernal longings blending,
That rises from the ponds and pools,
And seems at times unending

~ John Burroughs, “The Song of the Toad”

This is the second in a series of monthly blogs that will showcase progress on ACLT’s conservation and research efforts as well as highlight currently-active frog species. Stay tuned to receive updates! Read Frog Blog #1 here. You may also wish to subscribe to our blog here: www.acltweb.org

Spring has sprung! Over the past few weeks, the weather has warmed, birds have sung, flowers have bloomed, and more and more frogs have left hibernation to serenade listeners with jubilant nighttime song. At ACLT, wood frog and spotted salamander eggs have appeared in our vernal pools and recent evenings and cloudy days have been filled with the croaks and peeps of thousands of singing frogs.

The prevalence of these wonderful animals is great news for the Parkers Creek watershed! Not only do they take care of bothersome insects, but frogs are also considered indicator species, so their presence “indicates” the health of an ecosystem. While they have lungs, frogs can also breathe through their skin (and therefore breathe while underwater), allowing them to have added protection from terrestrial predators and to hibernate undisturbed in aquatic environments. However, breathing through their skin also makes frogs especially susceptible to harmful pollutants since they may also absorb unwanted chemicals or diseases. The Parkers Creek watershed appears quite healthy since our frog populations are not suffering from contaminants and are instead thriving and growing!

More precise information about the type of species and number of individuals present at ACLT is being gathered through my capstone project. University of Maryland scientist Dr. Christopher Rowe, dedicated volunteer Kevin Donahue, and I set up several drift fences along an existing vernal pool on the PF2Bay trail and along one of the two new vernal pools installed last month. These fences, made from aluminum sheeting and tobacco stakes, are about 12 feet long and prevent amphibians from walking (or hopping) directly into the vernal pools. Instead the fences guide the amphibians into buried coffee cans where they are trapped for a short period of time until volunteers come to documents and release them. Volunteers will monitor these cans daily for two weeks each month from April to June and count and identify the species present. When there are multiple days in a row when monitoring cannot take place, the cans are covered and amphibians can freely move around the fences.

Frog call surveys are also being conducted periodically in the evenings. These require someone (myself or one of ACLT’s fantastic volunteers) to stand by the vernal pools at night and record which species of frogs they can hear and the intensity of their song. This data allows us to know what species are active at ACLT and get a rough idea of the number of individuals, even if we cannot see the animals. Data is also reported to FrogWatch USA, a program run by the Association of Zoos and Aquariums, where it joins a national database and can be used for larger science and conservation projects.

Through these monitoring efforts and from periodic visual observation (including the amazing Master Naturalist herp hunt on March 24^th), we have seen a lot of species in ACLT’s vernal pools. Spring peepers, wood frogs, green frogs, and southern leopard frogs have been out and about, as have other amphibians like spotted salamanders and eastern newts! While the two manmade vernal pools I constructed last month (with LOTS of help from some amazing volunteers) have yet to have any breeding amphibians, recent rains filled the pools, and some insects and a spring peeper have moved in. Soon, these pools should be teeming with life, just like nearby natural areas!

Last month, I highlighted some of the frog species that may be active the earliest: spring peepers (Pseudacris crucifer), wood frogs (Lithobates sylvaticus), upland chorus frogs (Pseudacris feriarum), pickerel frogs (Lithobates palustris), and American toads (Anaxyrus americanus). These species will likely all still be calling throughout April, except for the wood frogs which complete their breeding season within just a few days. This month, many more species will emerge (or already have emerged) from their hiding places underground to join in the raucous evening symphony. Some of these species include the southern leopard frog (Lithobates sphenocephalus), the gray treefrog (Hyla versicolor), Cope’s gray treefrog (Hyla chrysoscelis), the Fowler’s toad (Anaxyrus fowleri), and the green frog (Lithobates clamitans). More information about these wonderful species and links to hear their calls can be found below!

Additional Southern Maryland Frog Species Active During April

Southern Leopard Frog (Lithobates sphenocephalus)
The southern leopard frog is the most common true frog species in the Coastal Plain, often found around backyard ponds and vernal pools (seasonal wetlands that only fill with water for part of the year). They have dark, roundish spots on their backs (hence the name leopard frogs), range in color from green to brown, generally grow to about 2-3.5 inches, and have two lighter-colored dorsolateral folds (raised lines) running down the edges of their backs. They greatly resemble the related pickerel frog, though their spots are less square and more uneven, and they lack the pickerel frog’s distinctive yellow patch on the inside of their thighs. Southern leopard frogs are great swimmers and may use their powerful back legs to jump into your local waterways! They are not very particular in the types of wetlands they occupy and may even be found in brackish (slightly salty) water. Listen for their chuckle-like call in the evenings or on cloudy days: Southern Leopard Frog Call

Gray Treefrog (Hyla versicolor) & Cope’s Gray Treefrog (Hyla chrysoscelis)
The gray treefrog and the Cope’s gray treefrog look identical to the naked eye and can only be differentiated through genetic analysis or by call by a trained listener. Both species are generally gray or green (and can change color in a few hours depending on their environment) with darker blotches on their backs. They are fairly small and generally only grow to 1-2 inches in length. Like all treefrogs, (Cope’s) gray treefrogs have slimy skin and large toe pads to facilitate climbing, though their skin is rougher than most other treefrog species. Since the two species resemble each other so closely, researchers are unsure how much the ranges of gray and Cope’s gray treefrogs overlap, but the two species together inhabit much of the central and Eastern US. Look for them in trees or even on manmade structures like your fences or deck. Both of their calls sound like fast, high-pitched trills, though the Cope’s gray treefrog’s call is a bit higher and faster. You may hear them singing in the evenings near vernal pools which are their favorite breeding areas: Gray Treefrog Call and Cope’s Gray Treefrog Call.

Fowler’s Toad (Anaxyrus fowleri)
Fowler’s toad is one of the two true toad species found in Maryland, the other is the American toad. Like the American toad, Fowler’s toads are usually brown with short back legs for hopping and glands on the side of their heads that excrete toxins. These toxins aren’t particularly dangerous to humans, though you may not want to rub your eye after picking up a toad. The easiest way to differentiate Fowler’s toads from American toads is by the density of bumps (or “warts”) on their bodies. Fowler’s toads usually have 3-4 bumps per dark brown patch, while American toads generally only have 1-2. Fowler’s toads are usually 2-3 inches long and breed in a variety of wetlands, especially those that are shallow and have sandy bottoms. You may see them hopping through forests or meadows or hear their calls that sound a bit like a sheep saying “baaaa” or a series of short, repeated yells: Fowler’s Toad Call

Green Frog (Lithobates clamitans)
The green frog is usually brown in color (confusing, I know), though often has green markings above its snout that resemble a mustache. They are a fairly large species growing to 3.5 inches in length and are often confused with small bullfrogs. Like bullfrogs, green frogs have a circular tympanum, or external ear, which is larger than the eye in male frogs and the same size as or smaller than the eye in female frogs. To differentiate between a green frog and a small bullfrog, look at the arch that comes out from the eye. If it curves around the tympanum, you have a bullfrog and if the arch continues down the side of the animal’s back, you have a green frog! The green frog generally likes to breed in permanent ponds, though I have spotted some in vernal pools and in small roadside ditches as well. Green frogs usually remain within 1 meter of water as adults (except on rainy nights), so wetlands are a great place to look for or hear this species! If you hear a deep groaning call in early spring, chances are it’s a green frog: Green Frog Call

I hope you enjoyed this month’s Frog Blog! If you are interested in learning more about these animals or want to get involved with amphibian monitoring efforts, please email me at nicole@acltweb.org.

Click to Read Frog Blog #3

April 9, 2021 By crm

Aphids: Life at the Base of the Food Chain

By Judy Ferris, ACLT Guest Blogger

This is the first in a series of blog posts providing a glimpse into the secret lives of insects that live among us – some friends, some foes. The author, Judy Ferris, describes herself as a born nature-girl, a gardener since the age of 10, and a birder for 45 years. Judy volunteers at ACLT’s Double Oak Farm as a ‘Flower Girl’ – a small team that manages several Flower Gardens. According to Judy, “It’s hard to be around flowers without noticing the insects they attract!” Hence the recent dive into the world of insects. Though still an amateur, Judy delights in learning about insects and sharing with others, the stories of these fascinating and vital creatures.

Let’s start our exploration of the insect world at the base of the food chain – with aphids! As we know, aphids are sucking insects, with specialized mouthparts to access sugary sap in the phloem (vascular tissue) of plants. To our eyes, aphids are rather featureless; like miniature balloons of sugar water with legs.

To would-be predators, however, each plump, hapless aphid is a hit of sugar in an easy-to-open container – soft and rubbery on the outside, juicy and irresistibly succulent within.

Aphids have been on earth since before the age of dinosaurs and are still going strong. How have these walking sugar-blobs survived so long while other, mightier species died out forever? Turns out that these tiny bugs have quite a few tricks up their skinny little sleeves.

Here in Aphid World, we are at the bottom of the food chain. If you are an aphid, you are a featured item on the menu of many insect species. Thus, there is one thing you need to do really well; reproduce quickly! Aphids have made rapid reproduction into an art form. How do they do this? The solution is unconventional, yet its simplicity harkens back to the aphid’s ancient origin; cloning!

Here’s how it works. In spring, aphids emerge from over-wintering eggs. All are females. These original females generate more female offspring asexually, giving birth to live young rather than laying eggs. Why wait around for eggs to hatch when you can pop out babies right away? Second-generation aphids are also females and may even be pregnant with a third generation of daughters before they themselves are born! Yes, that’s right – mothers giving birth to daughters and granddaughters!

With this ‘telescoping’ of multiple generations, aphids can multiply exponentially. It is estimated that under ideal conditions, with no predators, pathogens, or parasites, a single female aphid could produce 600 billion sap-sucking descendants in a single season!

Another unique aphid talent is their ability to poop sugar water (also known as ‘honeydew’)! Yes, aphid poop is the basis for the famous win-win relationship between aphids and ants.

Aphids poop honeydew for sugar-loving ants. Ants, in turn, may serve as soldiers to protect their coveted aphid herd from predators. Through adaptations like cloned babies and pooping sugar, aphids have survived on earth for 280 million years and will likely be here long after we humans have vanished.

Lest you are now having nightmares about planet Earth inundated with aphids… Not to worry! There are plenty of insect predators who relish a sweet aphid feast; Lady Beetles, Flower Fly larvae, parasitic wasps, aphid midges, and even ‘aphid lions’ (the larvae of Lacewings). We will meet some of these predators in the coming weeks. Fasten your seatbelts. It may be a wild ride!

Now available! Read the next installment in The Secret Lives of Insects – “Lacewings: Beauty and the Beastly Babies”!

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March 29, 2021 By crm

By Nicole Stevens, Chesapeake Conservation Corps Member

O, I love to hear the frogs
When they first begin to sing;
How they vocalize the bogs,
And vociferate the Spring.
How they carrol as they croak,
How they mingle jest and joke
With their solemn chant and dirge
On the river’s slimy verge.
– Harry Edward Mills, “The Early Frogs”

This is the first in a series of monthly blogs that will showcase progress on ACLT’s conservation and research efforts as well as highlight currently-active frog species. Stay tuned to receive updates! You may also wish to subscribe to our blog here: www.acltweb.org

After weeks of rain, snow, and freezing weather, spring has finally begun for some of our amphibian friends! On Saturday, February 27th, spring peepers were heard during an evening guided hike at ACLT – the first frog calls noted in 2021. Soon, many more of Maryland’s 20 native frog and toad species will join in these nighttime songs as each of their breeding seasons begins. So, who are the frogs we hear calling in the evenings? And what is ACLT doing to conserve and research these important species?

The word “amphibian” means “double life” and refers to a group of animals that have aquatic larval stages generally followed by terrestrial, or land-dwelling, forms. The class Amphibia encompasses the orders Caudata or Urodela (the newts and salamanders), Gymnophiona or Apoda (the caecilians; a group of burrowing worm-like creatures with slimy skin and no legs), and the most commonly known: Anura (the frogs and toads). Many of these species utilize seasonal wetlands (often called vernal or woodland pools) as breeding sites since these pools are generally dry for part of the year, making them uninhabitable for permanent aquatic predators like fish. During their mating season, male frogs will “sing” to attract females who will then deposit fertilized eggs at these seasonal pools, or sometimes into more permanent ponds. Frog eggs are usually found in loose clumps, while salamander eggs are usually attached to surfaces (like sticks or leaves), and toad eggs resemble beads on a string.

Frog breeding periods vary slightly each year depending on weather conditions like temperature and precipitation. In southern Maryland, there are four active frog species you may be able to see (or hear) in March: the spring peeper (Pseudacris crucifer), the wood frog (Lithobates sylvaticus), the upland chorus frog (Pseudacris feriarum), and possibly the pickerel frog (Lithobates palustris), though the latter will likely not be active until April. There also may be a chance to hear American toads (Anaxyrus americanus), but they also will most likely not be out until April and May. Links to hear the calls of these species and more information about them are included below! Try to figure out what species are in your neighborhood (though remember not to handle them as their skin is very sensitive and many species also secrete irritating toxins).

As one of the two Chesapeake Conservation Corps Members working at ACLT this year, I am focusing on amphibian conservation for the program’s capstone project. A few weeks ago, I was awarded grant funding by the Chesapeake Bay Trust to install two new vernal pools, create educational signage and activities, and perform drift fence and frog call biodiversity surveys. I am happy to say that with the help of six wonderful volunteers, including University of Maryland herpetologist, Dr. Christopher Rowe, the first vernal pool was installed on March 3rd! This site is near existing vernal pools along the PF2Bay trail that are heavily utilized by breeding amphibians, so it will offset breeding pressures experienced at these two sites.

A second vernal pool was installed on March 12th with the help of five volunteers! This seasonal wetland is slightly further from existing pools – creating a new breeding site to increase the range of these important species, many of which are threatened. Both manmade vernal pools were made by digging shallow depressions in naturally low areas and installing 15-foot by 25-foot pond liners. They will be filled with spring showers and may attract amphibians throughout the spring and summer. By installing pond liners, these woodland pools will serve as important breeding sites for frogs, toads, and salamanders for decades to come.

The first frog call survey was also completed on March 2nd and 3-4 spring peepers were heard calling, despite the weather only being 31˚F! Data for these surveys are reported to FrogWatch USA, a program run by the Association of Zoos and Aquariums to form a nation-wide database for researchers, conservationists, and other interested people.

Southern Maryland Frog Species Active During March (click to enlarge photos)

Spring Peeper	Spring Peepers (Pseudacris crucifer) Spring peepers are the first frog species to emerge from hibernation each year, due to the natural anti-freeze in their blood that makes them especially cold-tolerant. They are quite small (only 1-1.5 inches long), usually brownish or greenish in color, and have a dark X-shape on their backs. Spring peepers are a type of treefrog with smooth, slimy skin and terrific climbing ability, though they generally remain hidden in leaves and brush on the forest floor. Listen for their high-pitched calls near waterways or forests at dusk. Each frog may call more than 20 times per minute! Click to hear the Spring Peeper call.
Wood Frog Wood Frog Eggs	Wood Frog (Lithobates sylvaticus) Another frog species to leave hibernation early is the wood frog, which emerges in late February or early March, depending on weather conditions. Wood frogs are tan with an area of dark brown behind their eyes that resembles a mask. They are much bigger than peepers, growing up to 3.25 inches in length, and are obligate vernal pool species, meaning that they require temporary wetlands to breed and cannot coexist with many permanent pond-dwelling species. Wood frogs are explosive breeders that only mate for a few days out of the year and produce many eggs at once. They were spotted at ACLT on March 10th and some wood frog egg masses are visible in the vernal pool along the PF2Bay trail! The coolest fact about the wood frog is that they are the only frog species known to live north of the Arctic circle and they survive the frigid winters using a unique series of adaptations. During hibernation, their hearts stop beating and they cease breathing as ice encases their bodies. They are able to survive using special compounds in their cells that prevent internal freezing and dehydration. In the spring, their bodies thaw and their breeding cycle begins. Listen for their quack-like calls in the evenings: Wood frog call.
Upland Chorus Frog-Photo Credit: Virginia Herpetological Society	Upland Chorus Frog (Pseudacris feriarum) The upland chorus frog is a small treefrog species that grows up to 1-3/8 inches and may begin breeding in late March in Southern Maryland. They are usually brown or gray with variable patterns, potentially including stripes or spots. However, they all generally have a dark stripe on each side of their bodies passing through their eyes and bumpy skin. Upland chorus frogs are more tolerant of anthropogenic disturbances than many other frog species, and may breed in human-generated habitats. Click to hear the Upland Chorus Frog call.
Pickerel Frog	Pickerel Frog (Lithobates palustris) The pickerel frog is in the family Ranidae, meaning it is a type of “true frog” that has many adaptations for life in the water, including webbed feet, long legs, and the absence of toe pads that facilitate climbing. Pickerel frogs are generally 2-4 inches in length and are green or tan with a number of darker brown splotches. The pickerel frog resembles the leopard frog (also found in this region) but can be differentiated by its square-shaped spots and the bright yellow markings near its hips (easily seen when the frogs jump). They secrete a substance that is dangerous to their predators and can be irritating to humans, but this species is very beneficial to the ecosystem by consuming otherwise-dangerous insects. Pickerel frogs hibernate in muddy pond bottoms and are usually most active in April, though if you’re lucky you may hear some at the end of March! Their call sounds a bit like a human snore: Click to hear the Pickerel Frog call (with a chorus of spring peepers in the background)
American Toad	American Toad (Anaxyrus americanus) The American toad is one of two true toad species found in southern Maryland. It is up to 4.4 inches long and has dry, bumpy skin and short back legs used for making small hops instead of the long leaps characteristic of most frog species. The American toad usually has 1-2 dark spots per colored patch on its body, differentiating it from the Fowler’s toad which generally has 3-4. In southern Maryland, American toads are usually active throughout April and May, though it is sometimes possible to hear them calling in late March. Look out for them in your nearby forests, or even your backyard! Click to hear the American Toad call.

For more information, check out these links:

Maryland’s Frogs and Toads (Order Anura) – Maryland DNR

Spring Peepers – The National Wildlife Federation

Wood Frogs – Animal Diversity Web – Virginia Herpetological Society

Upland Chorus Frogs – Virginia Herpetological Society
– Maryland DNR

Pickerel Frogs – Virginia Herpetological Society

American Toads – Animal Diversity Web

Click to Read Frog Blog #2

February 4, 2021 By crm

By Nicole Stevens, Chesapeake Conservation Corp Intern

This past year, our national symbol was caught on film at ACLT! Thanks to trail camera footage captured by ACLT volunteer Ian Messent, bald eagles have been taking over one of the feeder streams into Parker’s Creek. These majestic birds have been seen standing on logs, bathing in the water, flying, and even inspecting our trail cameras with great interest. Trail cameras provide us with the unique opportunity to see into the natural lives of wild animals, totally unaltered by the presence of humans. With this footage, we can really see what our local eagles are up to!

Several Founding Fathers decided upon the bald eagle for the US in 1782 as a symbol of strength and freedom, and Native Americans regard them as sacred and continue to ascribe them spiritual importance today.

Bald eagle numbers were greatly diminished in the early- to mid- 1900s due to hunting and pesticide use that decreased their ability to reproduce. However, bald eagle numbers have been growing since the 1970s and they transitioned from being classified as an endangered species to a species of least concern in 1995, according to the U.S. Fish and Wildlife Service.

Bald eagles primarily eat fish that they either hunt themselves or scavenge from other birds, though they will opportunistically feed on birds, small mammals, and carrion. They generally reside near bodies of water where they construct huge stick nests in tall trees. The largest bald eagle nest on record was 9.5 feet across and over 20 feet tall!

At ACLT, bald eagles can be seen fairly frequently near Parker’s Creek, and Alyssa Matanin (the other CCC intern) and I recently saw quite a few flying there and landing in trees. Since bald eagles are common around larger bodies of water, their presence at Parker’s Creek is unsurprising as it is their ideal habitat and many birds migrate from northern regions to winter in areas like these. However, their presence shown by the trail cam footage was slightly more unexpected, as they are further from a large body of water and in a more densely forested area. It is very exciting to see the bald eagles using this space and to have the opportunity to capture their natural behaviors on film.

Sources: