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Sunday 26 September 2021

A Walk in Dora Kelley Park

Photo credit: Rick Gutleber (link)

Yesterday, Charles Smith, a naturalist and ecologist led me and a group of other Arlington Regional Master Naturalist trainees on a walk around Dora Kelley Nature Park. He taught us about some of the native plants we were seeing along the trail, and shared some insight into what makes a healthy natural system, or a good habitat for wildlife. 

  1. There is biodiversity of tree and plant species. 
  2. There is a lack of invasive species.
  3. There is variety of tree ages (older, mature trees along with much younger trees). 
  4. There is a year-round natural stream.
As it turns out - if you love animals, you also love dirt. Soil along with the bacteria and fungus networks in the soil are a huge part of what makes a healthy ecosystem that can support all kinds of wildlife. Trees are feeding the soil as well as taking from it - they release some of their sugars into the ground which feed bacteria and fungus systems that then benefit the trees and the whole food chain. 

Charles also talked about how a disturbed ecosystem - one that has been clear-cut, flooded, fire-suppressed, or fragmented is much less able to resist the invasion of foreign species. 

Some invasive plants like garlic mustard actually are allelopathic - which means they produce chemicals that prohibit the growth of other plants. This invasive species is especially problematic because it prevents other plants from growing near it. 

Garlic Mustard. Photo credit: wikipedia user sannse (link)

All invasive plants hurt biodiversity of wildlife because they aggressively take up resources but don't feed insects which would then feed birds, reptiles and mammals. 

Fragmentation is another problem - human activity increasingly fragments natural areas with roads and development. Some species have evolved to only live deep inside a forest - but unfortunately they cannot survive in smaller and smaller fragments. Edge species, those generalists that do well at the edge of two types of habitats (think deer, raccoons, blue jays), proliferate in edge habitat, which has its own consequences. 

Deer overpopulation inhibits biodiversity, as deer love to eat tree saplings and browse shrubs and understory vegetation, which otherwise would provide homes and food for many other species. The topic of deer population management is controversial because they are so beautiful - but when we remove the predators of a species we then are responsible for keeping populations in check ourselves. Fairfax county has a safe and effective archery program. Arlington needs to follow suit. 

We also got to learn from Matt Neff, naturalist and animal keeper at the National Zoo in the Reptile Discovery Center. He spoke to us about herpetology - the study of amphibians and reptiles, and showed us how to properly roll logs to find critters. If you do this, it is very important to roll the log back into place after you are done! The ecosystem under a log is particularly hospitable to critters because it retains moisture and provides shelter from predators and weather extremes. 

Matt recommends the Salamanders of the United States and Canada field guide, Peterson's Field Guide for Reptiles and Amphibians, and the Lizards/Snakes of the Southeast (along with their other books in that series). He also suggested anyone with interest join the Virginia Herpetological Society to participate in surveys. Their website is also very helpful for finding information. 

While rolling logs, we found a worm snake! Worm snakes are fossorial, meaning they live underground, and eat earthworms. They look a bit like worms but are actually snakes. 

Photo credit: Tina Dudley

It was hard to get a close up photo of his face, so for reference, this is what their face looks like:
Photo credit: Flikr user cotinis (link)

Then we had a wonderful presentation on native plants by volunteer and ARMN member, Valerie LaTortue. This article describes the incredible work that Valerie has accomplished in the garden, with the help of many volunteers. 

While gardening in the demonstrative native garden at the Dora Kelley Nature Center, we also came across a few other exciting herps.

Photo credit: Tina Dudley

This gorgeous turtle is a box turtle. If you ever find a turtle on the road, move them to the other side of the road in the direction they were facing. 

We also saw a few DeKay's brownsnakes, (below), some common skinks and even a couple Mediterranean geckos (an introduced species, not pictured). 

Photo credit: Tina Dudley

Photo credit: Tina Dudley

Dora Kelley is unusual in northern Virginia, sadly, because it is a good natural system. It could be better if it had more understory plants, but it is an example of a solid, stable ecosystem. Check out this trail guide for some interpretation of what you see on your walk. Nature center is hopefully re-opening next month, so its a lovely place to take kids. They have some lovely reptiles inside you can examine more closely, no log-rolling needed.

And wherever you live, consider planting more natives in your yard or garden. Or at least avoid invasive plants like english ivy! Help out your local wildlife. 


Sources:

Charles Smith

Matt Neff


https://www.chattnaturecenter.org/visit/experience/wildlife/animal-facts/eastern-box-turtle/

Sunday 19 September 2021

Butterfly Count Highlights & Learnings

 This weekend  I went on my first Butterfly Count, organized by Audobon Virginia, but the data will be sent to the National American Butterfly Association (NABA). 

For this survey we visited Glencarlyn Library, Glencarlyn Park, Bluemont Park, Bonair Park, and the W&OD Trail.

Here are my favorite photos of the day (click to see a larger image):

Cabbage White

Eastern Blue Tailed

Eastern Blue Tailed

Monarch

Pearl Crescent

Silver Spotted Skipper

Variegated Fritillary

Fiery Skipper

Clouded Skipper

I had a great experience. Audubon put on a very helpful webinar a few days prior to the count to help train us on common butterflies in Virginia. I even got a copy of the new local field guide at the picnic after the count, signed by one of the authors - Judy Gallagher! It's hard to believe how much I learned about butterflies in 4 days. Some things that stuck out: 
  • Not all butterflies are bright/large - skippers are quite small, and some butterflies are brown or grey. 
  • You can tell a butterfly from a moth by the antennae - butterflies have slender antennae while moths often have larger or feathery antennae. 
  • The bulbs at the end of the antennae are called clubs - and they are important for identification. 
  • A butterfly's antennae can be "checked", or striped, see the Pearl Crescent above. 
  • The cloudless sulphur butterfly is a large yellow butterfly that seems almost a light green at times, no markings, and is very common in the area. I have never heard of or seen this butterfly before Saturday, but on Saturday I saw at least 5! Amazing what is right in front of us that we just don't notice. 
  • All butterflies have a host plant, which means its the  plant they usually like to lay their eggs on  - for example, the host plant of a viceroy (a monarch look-alike) is a willow tree. 

Friday 17 September 2021

Raccoon, Procycon lotor

Some trees are anachronistic - meaning that scientists believe they have lost the species that co-evolved as their seed disperser. Avocados are the first to come to mind. The American persimmon tree, Diospyros virginiana, is another example - scientists found that after passing through an elephant, persimmon seeds increased germination success and sprouted faster. 

Photo credit: Gregory Thompson

Luckily, we still have raccoons, procycon lotor, which are able to eat and pass persimmon seeds with successful germination, who are keeping this lovely native fruit in the ecosystem. While white tailed deer love to eat persimmons, they are not effective dispersers. So the deer, oppossum, foxes and birds can all thank the common raccoon for propogating this excellent food source. 

Persimmon fruit.
Photo credit: Koshy Koshy (link)

This past week, I went to the lovely Huntley Meadows in Alexandria for the first time. It is a gorgeous wetland with extensive boardwalk trails. There are frogs, turtles, snakes, herons, wood ducks, wild turkeys and, perhaps most charming - raccoons, eating persimmons. 

Video credit: Gregory Thompson

Raccoons hands evolved to help them find food buried in the mud on the banks of rivers and lakes in South America. Their paws are extremely sensitive, with 4-5x more mechanoreceptor cells  (cells that help them detect mechanical signals such as change in pressure) than found in most other mammals. Humans and primates have similar numbers of these cells. Some animals prioritize certain senses - for example, in owls their hearing is their dominant sense. For raccoons, 75% of their brain's sensory processing power is devoted to touch, more than any other animal studied. As omnivores, this evolved to help them find and identify many different types of food.

Despite their scientific name (lotor means to wash), it is actually a myth that raccoons wash their food.  What they are actually doing are feeling their food to identify it, but because they so often hunt at the edge of the water, it can appear to us that they are washing or softening their food. There is evidence that water improves the tactile nerve response in their paws - so what looks like washing is actually the raccoons trying to "see" (feel) their food better.  

Their hands also make them excellent climbers, scaling trees and navigating branches with ease. They even have a unique ability, when descending trees headfirst, they are able to rotate their hind feet a full 180 degrees, so they are pointing behind them, to aid in their descent. 

Photo credit: Tina Dudley

There are three species of raccoon, all of which look fairly similar to each other, however the pygmy raccoon in Mexico is critically endangered.  The common raccoon, procycon lotor, is of least concern, with a population that has exploded since the 1940s. Their closest living relatives are the ringtail, coati, and olingo - other species of the family procyonidae. The divergence of raccoons and ringtails is thought to have occurred about 10.2 million years ago. 

Raccoons typically have 1-7 young, called kits. The Wildlife Rescue League describes the early life of a young raccoon as follows: 
When hungry, cold, or not in contact with another warm body, the cubs will start chattering, whine or twitter like birds. They can crawl in a spider-like fashion with all four legs in extension, but cannot climb or stand and support their full weight. The eyes open at about 21 days, the ears shortly thereafter. They will be very vocal at this age. They will churr, growl, hiss, and give an alarm snort. When five to six weeks old, most can walk, run, and climb very well. Seven-week-old cubs will engage in active (and sometimes rough) fighting characterized by growling, squealing, biting, wrestling, and imitating adult defense postures. After about eight to nine weeks of age they begin eating solid foods in the wild and begin traveling with their mother.
Photo credit: Pixabay, user pacificairforce (link

Too often we think of the wildlife that lives near us as pests, and romanticize wildlife that lives elsewhere. When you go to the zoo, you rarely see or learn about native species, or how you can support wildlife by cultivating native plants in your yard. The next time you have raccoons in your attic or in your garbage, take a moment to be impressed by how successfully this animal has adapted to the human environment. And if you need a reminder of how lovely this animal is, stop by Huntley Meadows in August or September and join the herd of photographers capturing this charismatic critter. 

Photo credit: Tina Dudley

Sources:



Friday 10 September 2021

Abe, the Eastern Copperhead Snake

Photo credit: Peter Paplanus (link)

Some people are afraid of the Eastern Copperhead, Agkistrodon contortrix, but they don't need to be. While this a venomous snake that should be respected and given ample space if encountered - this species of snake is very rarely fatal to human or pets. 

As a kid I grew up hunting for garter snakes in my backyard, and later adopted a ball python of my own to the great discomfort of my mother. I find them fascinating and beautiful instead of scary. Even venomous snakes have evolved their venom to hunt prey, not to terrify humans. If we stay out of their way and take a few safety precautions, we will be just fine. Use a headlamp when retrieving firewood from your pile out back or when hiking around sunset. 

Only three of the 32 species of snakes found in Virginia pose any danger to humans. If you enjoy spending time in nature, it is a good idea to be able to identify them. 

Meet Abe - Animal Ambassador at the Potomac Overlook Nature Center

Abe fascinated me because he is a very active snake that slithers right up to the glass to investigate new people, likely thanks to his heat sensing organ that all pit vipers have between their eyes and nose. 

Abe is an animal ambassador that helps people learn how to recognize this snake in the wild, and educates them about the importance of snakes to the ecosystem. 

Here is a video of him.

Sorry about the picture quality below, the glass on his tank is fairly scratched up. 


It's hard to see in his photos, but in person it is easy to notice a sizable bump on his head. This was a result of a healed injury that happened prior to his capture. A vet has checked it out, so he is ok. 


Abe is an adult Copperhead, the staff are unsure how old he is because he has been at the Center longer than any of the current staff. They guess he is between 5 and 10 years old. As a venomous snake, he is never handled, so they don't know exactly but would estimate he weighs only half a pound. Copperheads do not get super large - at most they grow to be 2-3 feet long. 


Copperheads, like most venomous snakes, have keeled scales and cat-eye pupils. Their habitat varies, according to the National Zoo website:
Copperheads live in a range of habitats, from terrestrial to semiaquatic, including rocky, forested hillsides and wetlands. They are also known to occupy abandoned and rotting wood or sawdust piles, construction sites and sometimes suburban areas. They climb into low bushes or trees to hunt prey and will also bask in the sun and swim in the water.

They are most active after sunset, especially on rainy evenings, when they hunt for prey including mice, birds, amphibians and lizards. 

Some interesting facts about this animal:
  • It is possible for copperheads to have a "virgin" birth through a process called parthenogenesis, a form of asexual reproduction where an unfertilized egg can develop to maturity.
  • Copperheads lose and replace their fangs up 5-7 times in a lifetime. 
  • Young copperheads are more grey than copper, and have a bright yellow tail that is used like a lure prey into striking distance, this color fades as they get older
Photo Credit: Patrick Feller (link)
  • Copperheads are ovoviparous, meaning eggs develop in the body and hatch inside or immediately after being expelled. 
  • Copperheads are social snakes and may hibernate in communal dens with other copperheads, as well as other species of snakes, such as timber rattlesnakes and black rat snakes. They tend to return to the same den year after year.
  • Males are aggressive to each other during mating season in front of females. 
  • These snakes can live up to 18 years in the wild, or up to 25 years in captivity!
Snakes are an important part of the ecosystem, both as predators and as prey. They are rarely dangerous to humans - in fact, their venom has been used to make medicine that helps people. Check out some of these articles below for more info, and I encourage you to visit Potomac Overlook to say hi to Abe and the other animals that live there. 

Sources:

https://www.virginiaherpetologicalsociety.com/reptiles/snakes/copperhead/copperhead.php

https://www.livescience.com/43641-copperhead-snake.html

https://nationalzoo.si.edu/animals/northern-copperhead

https://www.livescience.com/23103-virgin-births-common-wild-snakes.html

https://savethesnakes.org/2018/05/09/protect-venomous-animals/

Tuesday 7 September 2021

Smooth Earthsnake at Twin Oaks Intentional Community

After nature camp, I stopped at Twin Oaks intentional community in Louisa County to visit a few friends. Twin Oaks is one of the largest and oldest (founded 1967) still running examples of an egalitarian, income-sharing intentional community in the United States. 

The largest threat to wildlife populations is loss of habitat - and housing development contributes to that loss. There is only so much space and as our population continues to grow, we have to find alternative ways of sharing land and resources. 

Twin Oaks is home to 70-100 people (their population varies) on 500 acres of land, most of that is preserved woodland that is home to all kinds of animals. The community owns and shares vehicles, grows much of its own food, and uses solar as part of its energy package (the cows love to sit in the shade of the solar panels). 



While I was at Twin Oaks, I found a neat little snake, which I later identified as a smooth earth snake, Virginia valeriae. Virginia is home to 32 species of snakes, only 3 of which are venomous. 


The smooth earth snake is a small snake, at full size it can be up to just 13 inches long. They may also be a reddish brown or tan color. The "smooth" in their name differentiates them from the rough earth snake, which looks similar but has keeled scales (meaning each scale has a ridge in the center). 

These snakes spend much of their life underground, feeding on earthworms! They can be found under leaf litter, boards, logs or rocks. This snake species is viviparous, meaning the females give birth to live 2-9 live young! This species of snake is active year-round, except during periods of extremely cold weather. 

I have always loved snakes and even had a ball python of my own as a teenager, so it was very neat to stumble upon this cute little guy. I let him go after taking his photo for identification. 

I would recommend getting to know more about the snakes that inhabit Virginia - you can read about them all here and even take a snake quiz here! If you want to check out some other species of Virginia native snakes in person, I would recommend a visit to the Nature Center at Potomac Overlook Regional Park. More to come on the animals that live there in my next post!

Sources:

A Guide to the Snakes and Lizards of Virginia. Special Publication Number 6, Virginia Department of Game and Inland Fisheries. 

https://en.wikipedia.org/wiki/Intentional_community 

https://www.virginiaherpetologicalsociety.com/reptiles/snakes/eastern-smooth-earthsnake/eastern_smooth_earthsnake.php