Bald Eagle Surprises Great Blue Heron

 

One of the best things about participating in Arlington Regional Master Naturalists is getting to meet some really wonderful people - fellow nature nerds. One of my classmates, Kelly Geer, a former Wildlife Biologist and all around cool person, was kind enough to share this footage above with me for use on this blog. (Thank you Kelly!)

Kelly first noticed the fish in the water that seemed to be swimming strangely, on its side. Then upon closer inspection, she realized it was actually dead and floating, with turtles nibbling on it from below, pushing it forward. Then, the Great Blue Heron (GBH) (the largest heron in North America), stole the fish from the turtles and attempted to eat it. While GBHs prefer live prey, they are not above opportunistic scavenging. As seen in the video above, the GBH attempts to swallow the fish, but has trouble because of its size. It appears to be dunking the fish into the water in an attempt to lubricate or reposition it. The heron is smart to be cautious, as choking to death is a real danger for this bird. It's long slender neck, which gives it the powerful spear hunting method, also makes it difficult to swallow bigger prey and its possible the food can get stuck, killing both animals. 

Suddenly, a bald eagle swoops in. 

While the Bald Eagle has an excellent marketing team, the truth is that these birds often steal food from smaller birds, so it may have been trying to steal the fish. However, some sources suggest that Bald Eagles are occasional predators of adult Great Blue Herons - so that could also be what is going on. Based on the dramatic expression and quick exit made by the GBH, it seems the heron did not want to stick around to find out if the eagle wanted his meal or to make him a meal.  The eagle doesn't try to find the dropped fish and seems to fly off after the heron. 

And then, Kelly told me with a smile, the turtles resumed munching. It sounds like a fable: The Turtles, the Heron & the Eagle - in which the turtles, despite their speed and size, are ultimately victorious in the battle for lunch. 

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Great Blue Herons are beautiful, fascinating birds. At 4.5 feet tall, they are taller than some children, but they weigh only about 5lbs (about the same weight as a pack of printer paper) because their bones, like most birds, are extremely lightweight. While flying they actually have a 6-foot wingspan! This photo of a young GBH looks like a dinosaur because, well, birds are dinosaurs. Paleontologists are agreed that modern birds are descendents of theropod dinosaurs. More on this exciting topic here and I would encourage you to share this fact with a small child that loves dinosaurs.  

This drawing of the skeleton of a Great Blue Heron in an old book, titled Osteologia Avium, depicts the impressive adaptations this species has made to survive. Here is a real skeleton, for reference, from the New York State Museum. 

Photo credit: Biodiversity Heritage Library (link)

That wild s-shaped neck evolved so they could pack a powerful and fast punch when spearing fish while they stand silently above in shallow waters. Macken Murphy talks more about how the GBH hunts in his Species Podcast episode on Great Blue Herons. The Great Blue Heron's famous colors help them blend in with the grey/blue sky above. All About Birds, a fantastic resource on birds by the Cornell School of Ornithology, lists the food on their menu as such:

"fish, amphibians, reptiles, small mammals, insects, and other birds. They grab smaller prey in their strong mandibles or use their dagger-like bills to impale larger fish, often shaking them to break or relax the sharp spines before gulping them down."

Another cool fact about Great Blue Herons is that, while they are solo hunters, they are actually social animals and nest in groups, sometimes just a few pairs but often larger groups with dozens of couples. Both male and female take turns incubating the eggs. The young can typically fledge about two months after hatching, but the parents continue to feed the young birds for a few additional weeks.

Photo credit: Flickr User Nature80020 (link)

This week in ARMN we are studying Ornithology - including how to bird by ear, why birds are so important (hint: many reasons), what we can do to help protect Eastern Bluebirds from its arch nemesis - the common and invasive house sparrow (aka HOSP to people in the know), and how caterpillars are a crucial food source for many types of baby birds because of their high levels of carotenoids. 

Fun fact: It takes between 6,000 and 9,000 caterpillars to raise one brood of 3 Carolina Chickadees. Source: Nature's Best Hope by Doug Tallamy

Pro tip: Oak trees host the most number of caterpillar species of any tree, 557! So if you are going to plant a tree, plant an oak. If you love birds, you can help them by planting natives, or at least not planting invasive plants that take up resources, crowd out natives and don't even contribute to the energy cycle. To find out what other plants you should put in your yard to help raise the thousands of caterpillars needed by local bird families - use the Native Plant Finder tool. 

Sources:

https://www.livescience.com/are-birds-dinosaurs.html

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

https://www.allaboutbirds.org/guide/Great_Blue_Heron/lifehistory

Nature's Best Hope by Doug Tallamy

https://www.nwf.org/Educational-Resources/Wildlife-Guide/Birds/Bald-Eagle

https://www.spokesman.com/stories/2010/mar/28/eagles-find-herons-easy-prey/

http://naturemappingfoundation.org/natmap/facts/great_blue_heron_k6.html

https://open.spotify.com/episode/6ntSNG1xvuVx2qOJ0hK1HD

Recommendation: Species Podcast

I listen to this podcast almost every day: https://www.mackenmurphy.org/species

Macken Murphy does a fantastic job digging into each animal species and finding the surprising, the curious, the unusual and the impressive characteristics about animals many of us overlook. 

Some of my favorite episodes are:

• His first episode, the Opossum
• Kea (a type of parrot)
• Archerfish (and his argument about fish intelligence)
• Fruit fly (possibly the most well studied animal on earth)

All of them are good actually, it is difficult to select favorites. This is the podcast that inspired me to begin this blog, so I highly recommend it. 

Coming soon: An article on Great Blue Herons & Bald Eagles, with a fantastic video clip courtesy of my friend and ARMN classmate, Kelly Geer. 

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://orchardpeople.com/soil-bacteria/#:~:text=But%20often%20some%20of%20the,%2C%20multiply%2C%20and%20then%20die.

https://www.nature.com/scitable/knowledge/library/restoration-ecology-13339059/

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

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. 

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:

https://onlinelibrary.wiley.com/doi/full/10.1002/ece3.3008

https://bioone.org/journals/southeastern-naturalist/volume-14/issue-1/058.014.0109/A-Test-of-Potential-Pleistocene-Mammal-Seed-Dispersal-in-Anachronistic/10.1656/058.014.0109.short

https://dwr.virginia.gov/wildlife/information/raccoon/

https://www.pbs.org/wnet/nature/raccoon-nation-raccoon-fact-sheet/7553/

https://www.livescience.com/52655-raccoons.html

https://www.yellowstonewildlifesanctuary.org/raccoon#:~:text=Raccoons%20are%20extremely%20good%20at,things%20with%20their%20front%20feet.

https://www.wildliferescueleague.org/animals/raccoons-facts-and-fancies/

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/

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