Butler Field Beauties

Shared by Melissa Donahue

Naturalist

melissa.donahue@nashville.gov 

Photos courtesy Melissa Donahue unless otherwise noted

I’ve been away for a while.  Happy family obligations at the first of the summer pulled me away from Nashville and I’m just getting back to Warner Parks.  I feel a bit out of sync.  Missed seeing the first tiger swallowtail, tasting a ripened blackberry and hearing the first cicada call.  To reconnect with the season and the Parks I hiked around Butler Field.  Will Chamberlain, a co-worker and wildflower enthusiast, was kind enough to join me.  We met on a foggy morning in August.

One of the first flowers we observed was Fogfruit - Phryma lanceloata.  This herbaceous perennial plant is ½–2' tall.  It’s a small plant but once you notice it, it seems to be everywhere.  Many different pollinators are attracted to the flower. The largest group of pollinators are a small to medium size flies which hover motionless in the air.

Fogfruit in bloom in Butler Field

We also noticed this pretty little Virginia buttonweed – Diodia virginiana-- at the edge of the field.  A native flower, it grows low and mats close to the ground.  Do not plant it in your garden, as it is quite invasive.

Virginia buttonweed in Butler Field

Although this plant is better known for the frost flower seen in November, it produces white flowers in August.  Known as White wing-stem, crownbeard, or frostweed, Verbesina virginica, it stands 3 – 7 feet with winged stems.  A native species, the little white flowers attract honeybees, butterflies and migrating monarchs.  Frost flowers form around the first frost. These flowers are formed around the stem and just above the ground during cold autumn nights.  This is caused when water is forced out of the stem during the first hard freeze resulting in ice formations.  

Frostweed in bloom in early August in Butler Field

Frostweed/"frost flower" in November

Passionflower vines, Passiflora incanata, were also blooming.  This is the state wildflower of Tennessee.  Once used to treat anxiety, it the host plant of the Gulf and Variegated Fritillary butterflies and nectaring plant for many other butterflies. The seed pod gives the plant its other name, Maypop.  This seed pod may pop when opened, revealing delicious seeds and giving this plant the name Maypop.

Passionflower or Maypop in Butler Field

Brown Eyed Susan – Rudbeckia triloba – is a Tennessee native of the sunflower family.  These plants bloom from mid to late summer. Although self-pollinating, the flowers attract bees, wasps, small butterflies and other insects.  It is a traditional Native American medicinal herb used by several tribal nations, believed to remedy colds, flu, infections and snake bites, among other things.

Brown-eyed Susan in Butler Field

Towering above our heads was the Ironweed – Vernonia Gigantea, a member of the Aster family which grows 3-10 feet tall. This showy native is a host plant for several moth species.Native Americans used the leaves and roots to make a tea used during pregnancy, childbirth and to relieve postpartum pain. 

Tall Ironweed in Butler Field

Ironweed is especially striking when a Swallowtail butterfly is drinking nectar from it. Photo credit Charlie Curry

Finally, the plants most of us are very aware of this time of year: Great Ragweed, Ambrosia trifida and Common Ragweed, Ambrosia artemisiifolia are coming in strong!  Common Ragweed grows 1-4 feet tall and Great Ragweed grows 3-12 feet tall.  Although known for causing hay fever, this plant has other uses.  Native Americans cultivated Common Ragweed as a source of food before maize, using the stalks to manufacture ropes and the leaves to prevent bleeding.  Common Ragweed effectively removes lead from the soil. The flowers of Great Ragweed can be crushed to make a red dye.  Today it is a seed source for many birds.

Great Ragweed

Common Ragweed

To visit Butler Field, park near picnic shelter #9 in Edwin Warner Park.  Head out for a stroll and let us know what you see.

Map of Edwin Warner Park to help you find Butler Field

 

No Holds BARS

No Holds BARS

Shared by Perri Haga
Warner Park Nature Center BIRD (Bird Information, Research and Data) Intern 
wpnc@nashville.gov

Photos courtesy of Laura Cook unless otherwise noted

My dad likes to say that if he ever wrote an autobiography, he’d call it “Mowing with Swallows,” because of the Barn Swallows (BARS) that love to swoop around him as his lawnmower stirs up insects for them to eat.  They’re fairly easy to spot in flight: just look for the characteristic forked tail silhouette and their graceful, swooping movements. 

Courtesy of Cornell Lab of Ornithology. If Barn Swallows were in the circus, they’d be acrobats for sure! 

Barn Swallows are a migratory species that spend their breeding season in North America during the summertime and head to Central and South America for the wintertime.  They nest in Warner Parks with the largest colonies at the Steeplechase barn and at the Nature Center. The next time you are at the Learning Center, turn your eyes upwards and you can see their nests made of mud on the sides of the building.

This nest is in the middle of a stall at the Steeplechase barn, and the babies are only a few days old!

Because of their choice of nesting location, some people don’t enjoy the presence of Barn Swallows, especially when nestlings start leaving huge messes behind… it can get gross!

However, I think that we should LOVE these birds! Not only are the adults majestic and the babies adorable, but they also are insectivores, providing us an amazing ecological service in the summertime by consuming incredible amounts of insects: around 34,000 insects per nestling!

Courtesy of Charlie Curry. Begging nestlings are a common sight at the Nature Center in the summer. You can hear them even before you can see them!

This summer, I was so excited to be the Warner Park Nature Center BIRD Program Research Intern through support from my college, Lipscomb University.  Because Barn Swallows are so reliant on man-made structures for their nests, depend on insects and are incredibly interconnected to us, they were a perfect species for me to study.  

How could you resist that little face!? This nestling is seven days old. His eyes and ears are open, and feathers are just about to emerge from the spines on his tail.  

This little guy wouldn’t stay away from his sibling!

There are three research techniques I used this year to get to know Barn Swallows better.  The first is when a federally permitted bander from the BIRD team places a lightweight numbered band on a nestling. Our hope is that one of these banded nestlings will be recaptured in South America and as they return to Nashville. This can help us learn about survivorship and migration. 

Before banding nestlings, we have to climb a ladder and bring everyone down in a basket.  These nests are high!

We use special pliers to put the band on so the nestling can’t even feel it. 

The second thing we do is assess survivorship from the time they hatch until they fledge (leave the nest). We do this by checking the nests regularly with a tool that looks like a suspiciously large dentist’s mirror! I do this three times a week to count eggs or nestlings, determine hatch dates, and track nestling growth. 

Using a mirror lets us see inside the tall nest without scaring the babies inside. 

The last aspect of my research is something that anyone can do: observation! I spend a lot of time watching the behavior of these birds, looking at how adults interact with each other, with their nestlings, with other birds, and more.  It’s fascinating how complex Barn Swallows are, and I discover new mysteries every day! 

Courtesy Charlie Curry. This bird hatched this nesting season. It has a paler face and hasn’t grown the long tail feathers typical of adults: a fun thing to observe! 

Most Barn Swallows will begin their migration south within the first couple weeks of August. 

 Keep an eye out for the last of these birds or look for the nests that they’ve left behind.  They’ll be back next spring and might even reuse these nests for a new year!

The Heart of Purple Martins

The Heart of Purple Martins
Shared by Heather Gallagher
Naturalist
heather.gallagher@nashville.gov
Photos courtesy Graham Gerdeman

As you have heard by now,  it has been a banner bird year at the Nature Center. The bluebirds, barn swallows and other insect eaters are visible and plentiful, especially if you choose to view them from the comfort of a rocking chair on the back porch.

And the martins-oh the purple martins! I have documented a minimum of 11 pairs and over 40 young at our site. But let's back up.

As a federally-licensed bird bander, I check our gourds weekly beginning in mid-May, each one yielding more nests, then more eggs, then more young.

Gourd with 6 beautiful eggs.

• By May 27, I counted 32 eggs in 11 gourds. 
• By June 2, there were 46 eggs. 
• The next week eggs had begun to hatch, and I counted 29 young.  

Babies, probably around 2 days old.

Young martins display no feathers. They are all about food, and have large beaks to show for it. As they age, feathers will begin to develop in the form of pins that serve as protection for the feathers.  

Our study at the Nature Center is two-fold: we participate in the Purple Martin Conservation Association's Monitoring Project as well as the Purple Martin Banding Project through the BIRD program. Documentation of nests, eggs and young is reported to PMCA yearly, while the BIRD program info is submitted to the USGS Bird Banding Laboratory in Maryland. 

The emergence of pin feathers is an indication that the birds are at the age to be banded, around 16-20 days. Believe it or not, the band will not fit correctly until the baby martin's leg is SMALL enough for it. 

Due to the close proximity of the nests, I decided on one date to band all babies, choosing the date that babies would be in that 16-20 day old window. The gourd rack was lowered, and staff removed babies one nest at a time.

Babies ready to be banded!

 As Master Bander Laura Cook, our BIRD program coordinator, recorded band numbers, I banded each baby.

Pliers are specially adapted to securely and safely close bands.

The band can turn comfortably, just like my wedding band!

After applying bands to the left leg, Master Bird Bander Sandy Bivens returned nestlings to their proper gourds. When all birds are banded, we hoisted the gourd rack back into position, and the adults returned with food in less than a minute. 

This week has been extra interesting around the martin gourds, as a hawk has been checking out the fledglings taking their first flight. 

Hawks are one of the many predators that threaten martins.

Our martins will leave soon, gathering at a roost before heading to Central and South America. Yes--they leave Tennessee over the winter, returning next March to begin again.

Now the roost is most curious: in Nashville, Purple Martins will gather by the thousands--maybe even hundreds of thousands--in downtown Nashville around the river. So when my husband shared that Heart would be playing at Ascend last August, I jumped at the chance.

And I was rewarded! While everyone was jamming to Ann and Nancy Wilson, I was looking skyward, amazed at these incredible birds as they spiraled above the Cumberland. There must have been 30,000 martins!

Purple Martins have definitely stolen my Heart!

Creek Exploration 101

Creek Exploration 101

shared by Naturalist Rachel Anderson

rachel.anderson@nashville.gov

photos credit Rachel Anderson

With the warm, humid days here to stay for a while, it’s definitely a great time to head to a nearby creek to cool off and have fun.  For many, it’s enough to feel the cool water on your feet, let the kids splash and build dams, maybe watch a leaf boat float along lazily.

Boats made of all natural materials can be fun to float down the creek

But the naturalist in me suggests another exciting idea – look a little closer, delve a little deeper, and discover what other animals (besides humans!) can be found in the creek.

Most people have caught crayfish and there are certainly plenty of these in our creeks.  But have you really looked closely at one?  How many legs do they have? What color are the pinchers? What other body structures do you see? What behaviors do you notice when you place it back in the water? 

It’s best to pick up crayfish right behind their front pinchers like this.

And there are other invertebrates (animals without backbones) that live in the creek and are pretty easy to find.  Gently lift a small rock and look closely at the underside.  Do you notice anything moving?  What shape is it? 

How many legs does this little creature have? Do you see the 3-prong tail at the end?

Don’t worry about naming your discovery, instead focus on what you can observe, what questions you might have, and what your discovery reminds you of! 

This interesting creature reminds me of a worm or a grub. It moves like one – shrinking and growing – but it’s white all over with an interesting ring of tentacle-like structures at one end. I wonder if that is the mouth? Is this the adult form or a larvae? 

This round insect is a water penny. Finding these indicates good stream quality, as they can only live in clean water. 

There are so many tiny creatures under these rocks, you may want to bring a clear cup for temporary viewing. A white ice-cube tray also works well.  If you gently sweep your finger across the insect on the rock, you can lift it up, then dip your finger in the water to release it into your container.

Want to find more interesting creatures? Place a net in the water, downstream of a rock where the water is moving quickly. Lift the rock and anything under may float downstream into your net!  If you rub the underside of the rock while it’s still underwater, you can dislodge tiny creatures as well.

As you pick up rocks and use nets to search, be on the lookout for vertebrate animals as well, like salamanders and snakes.  Most snakes in our river are harmless and quickly move away when disturbed. 

What do you notice about this snake we found in the creek one day?  We learned these reptiles, called queen snakes, eat crayfish because it regurgitated its meal when we caught it.  Probably a good idea to leave them be in the future!

Found a 4-legged friend? Be sure your hands stay wet when handling these sensitive salamanders.

How many different animals can you find during your exploration?  What do you wonder about them? Be sure to take pictures and videos of the animals you find, and then carefully release everything back into its habitat.  And be sure to come by the Nature Center with your questions and we can help you learn more about your discoveries!

Wildlife Encounters on the Burch Reseve

Wildlife Encounters on the Burch Reserve
Shared by Naturalist Kim Bailey
Photos courtesy Kim Bailey unless otherwise noted
kim.bailey@nashville.gov

This tunnel is  your entryway to the beautiful Burch Reserve. You never know what you will find there so put this trail on your to do list!

Walking through the tunnel at the Burch Reserve in early June, I spied a medium-sized rodent at the far end.  It ran out of the tunnel and up the hillside where it hunkered down in tall grass. Peering up through the vegetation, its mottled coat of stiff hairs and medium-length tail gave its identity away. I was thrilled to see my first living Hispid Cotton Rat (Sigmodon hispidus), not just a stuffed specimen.  Although considered common in Tennessee, these rats had never been documented in Warner Park. 

Hispid cotton rat hiding  in overgrowth on the Burch Reserve. It is facing left—see it’s pointed nose  far left near the center?

Cotton rats are in the same family as white-footed mice, voles, lemmings and hamsters. 

Hispid Cotton Rat courtesy Google images

They love grassy fields with shrubby overstory, so the Burch Reserve provides a perfect habitat for them. They make runways in the grass about 3" across, leaving little piles of shorn leaves at regular intervals. The name comes from the stiff ("hispid") hairs on their coat and the fact that they are often abundant in cotton fields. Cotton rats feed on grasses, sedges and agricultural crops, as well as insects, carcasses and the eggs and young of ground-nesting birds. In turn, coyotes, bobcats, hawks, owls and other predators feed on them. 

Cotton rats create  runs in the grass to move easily through their habitat. It takes a keen eye to notice the  3” wide trails.

It is always exciting to see something new in the Park and to add to our species inventory. Finding the cotton rat was a great beginning to our hike, but more discoveries were waiting on the trail.

As Melissa and I topped the ridge we noticed little clusters of butterflies spiraling up in what appeared to be a well-choreographed “dance”. After observing them for a few moments, we realized the butterflies were only in areas where a beam of light penetrated the canopy and illuminated the forest floor. Every now and then the butterflies (by now identified as Banded Hairstreaks) would descend and land on a leaf and then lean heavily to one side so that only one wing showed. I had never seen such behavior.  A later search of Rita Venable’s Butterflies of Tennessee taught me that the spiraling behavior was exhibited by males sparring over territory. As for the unusual angle they held upon landing, I could only surmise the males must be posing for nearby females!

This Banded Hairstreak landed and held this angled pose for long minutes before  joining  other males in sparring mid-air.

Now that our eyes were on butterflies, we noticed a Little Wood Satyr on the ground. This species rarely shows up on our butterfly counts, so we were happy that it was content to stay put as we took pictures. Little Wood Satyrs display an erratic flight just above the ground and appear very plain and brown in flight. However, when it lands you see its large eyespots.

As we began to descend the ridge, a bird dropped to the ground for a few seconds quite near us. The sunlight caught the feathers on its head, making it look almost florescent cherry! It was a Scarlet Tanager – a second year male based on his mix of red and yellow body feathers. The yellow female Scarlet Tanager was with him and we delighted in watching as she repeatedly flew to him, landed on a nearby branch and fluffed her feathers. She was clearly displaying to him, a display that we interpreted as readiness to mate. We laughed as this inexperienced male ignored her time and time again.

This second year male scarlet tanager is still in the process of changing into his adult plumage, from his yellow juvenile feathers into red adult feathers.

As we entered the field below Pickerel Pond we saw birds darting about a small fallen tree whose branches were sticking up above the tall grasses. When we got closer to the tree I was astonished to find a male Blue Grosbeak, a male Indigo Bunting and a Great Crested Flycatcher perched within a  foot or so of each other!  I cursed my decision to leave my good camera at home but vowed I would return soon to the beautiful Burch Reserve.

It’s not often you get to see a Blue Grosbeak and Indigo Bunting share the same tree! The Great Crested Flycatcher escaped before I could capture it on my iPhone.

Edwin Warner Park's Burch Reserve is open every day from dawn until 11 p.m. Dogs and running are not permitted in this very special natural area. 

Map of the Burch Reserve

Finally: Purple Martins

Finally: Purple Martins
Shared by Heather Gallagher
Naturalist
heather.gallagher@nashville.gov
photos courtesy Graham Gerdeman unless otherwise noted

I haven't lived in Nashville long--I moved here around 20 years ago. At that time, the Nature Center had just installed a Purple Martin gourd rack behind the building, and the staff hoped they would host Martins in every one of the 12 gourds.

But we didn't. For years, Martins were absent, or, if they did come, were driven away by European Starlings or Eastern Bluebirds. One year they even competed with Tree Swallows! Still, no Martins.

European Starling, a non-native competitor, and the Eastern Bluebird, a native cavity nester. 

Although a bad year for many of us, this year has been amazing for Purple Martins at the Nature Center. So I asked my friend and Nature  Center supporter Graham Gerdeman to photograph a nest check on a hot Tuesday morning in June.

Martins are cavity nesters, building their nests in holes in trees and fence posts. In the eastern US, they are found 99% in man-made housing such as metal houses or gourds.
They build nests out of straw and heavy grasses, and they place mud at the entry to the gourd. Finally, when the nest is complete, they place one final green leaf on top, kind of like the icing on the cake!

Martins will add mud to the entrance of the gourd as protection against predators

An adult male Martin adds a green leaf to his completed nest. 

Female birds are easy to distinguish from adult males: they have a white to creamy-white breast. Adult male Martins are fully black--almost purple! Females will lay several eggs; I have documented as many as 7 eggs in a clutch. When the last egg is laid, incubation begins, and the female will spend these hot, humid days keeping her eggs warm. She'll do this for a little over 2 weeks, then the first baby will hatch.

Five perfect eggs in this gourd! Martins in Warner Park have averaged between 3-7 eggs each season.

It's about 25 days until the babies leave the nest. Yes, they will fly right out of that gourd, launching themselves into the air over 15 feet above the ground.

Check back next month as we follow the life cycle of these amazing birds!