After dropping to a low of about 300 k in 1900, deer populations have recovered to about 30 M, which is possibly more than the pre-Columbian levels. The deer, in turn, are keeping the trees in check, nibbling on seedlings and giving space for other plants to grow. Populations have stabilized in some areas with the reintroduction of predators (bobcats, coyotes, black bear) which prey upon fawns. That seems better than watching an unchecked population starve after they've eaten all the available food.
2022-06-19 Algonkian Park, Sterling, VA
AKA the dogbane tiger moth, Cycnia tenera. Butterflies like monarchs defend themselves by having horrible taste and dressing in bright robes (aposematism). But these are night fliers, so looking fancy does no good. Instead they use colourful language, emitting a sequence of ultrasonic chirps to tell approaching bats that they are poison. Some moth groups with better taste have developed radar jamming instead, sending an echolocation response fast enough to confuse the bat about its actual location. It's amazing what you can accomplish with 65 million years of random bit twiddling.
2022-06-11 Audubon, PA
[1] Hristov and Conner (2005). "Sound strategy: acoustic aposematism in the bat–tiger moth arms race." DOI:10.1007/s00114-005-0611-7
The internets don't have much to say about it. It is a leaf beetle from the south east that feeds on nightshade family. In this case some sort of black nightshade that found itself in our garden (a weed that produces little black berries, but it might be native so I let it be).
2022-07-16 Bethesda, MD
Free-range domestic birds. If you habituate them to a roost you can let them roam free. They will travel a couple of miles, such as in this case over a highway and into an empty field but they will come back to sleep in safety. Note: Chickens (genus Gallus) are a domestic form of junglefowl (part of the pheasant family) whereas guineafowl are in their own family (Numididae). Both are in the order Galliformes, which is to say "chicken-like".
2022-06-11 Parkesburg, PA
Despite it being native, I can't say I'm pleased to have this guest show up in our house. Unlike the carpenter ants and carpenter bees the termites actually eat the wood with the help of protozoa in the gut to digest cellulose. They evolved from cockroaches to form complex social structures, developing a pheromone signaling system for communication. They are unrelated to ants, wasps and bees, evolving from cockroaches 100 million years earlier (150 MYA).
2022-06-10 Bethesda, MD
Introduced from Europe multiple times as a biological control agent, it is now naturalized in North America. There are plenty of aphids for it to eat in our garden.
2022-05-17 Bethesda, MD
A crane fly after the rain. It has very long feet hanging below the leaf. I like how the water forms drops on its shell, adding in some lensing. iNat suggests the tiger crane fly genus.
2022-05-07 Bethesda, MD
A little different from the western chipmunk (larger, longer lived, more territorial), but still much smaller than a squirrel. They make a constant "chip chip chip" which could easily be described as annoying.
2022-05-02 Locust Grove Nature Center, Bethesda, MD
Yet another WODU (#31, #59, #61, #88) because they look so unreal. Bird banding codes (WOod DUck) are handy shorthand if you are part of the Christmas bird count---it's faster to write the first couple of letters of each word than writing out the whole name. Unfortunately there are collisions (BarreD OWl and BarN OWl for example), so you have a list of exceptions to memorize and get wrong. Since I’m posting today from South Carolina I refer you to this article from the Carolina Bird Club.
A largish bird (300-400g), it is only little compared to the great blue heron (2100-2500g). I think it is eating a fish or maybe a dragonfly. Often young birds are drab and mottled making them harder to see but the little little blues are pure white. In this case it lets them blend in with flocks of snowy egrets for the first year before they start dining alone as adults.
2022-05-01 Huntley Meadows Park, Alexandria, VA
Forest birds which nest close to the ground so bird researchers like them. They are socially monogamous, but genetic testing shows high rates of "extrapair fertilization". Even with close following by the male during fertile periods a neighbouring male may still slip through (presumably while he is off on his own dalliance) or the female may evade long enough to diversify her brood.[1]
2022-05-01 Huntley Meadows Park, Alexandria, VA
[1] Chuang-Dobbs, Helen C., Michael S. Webster, and Richard T. Holmes. "The effectiveness of mate guarding by male black-throated blue warblers." Behavioral Ecology 12.5 (2001): 541-546. DOI:10.1093/beheco/12.5.541
Another flicker (see #367), this one an east coast male. Despite the large difference in feather colour between the red-shafted and yellow-shafted varieties, the genetic difference is small and they mate at random where the range overlaps.[DOI:10.1642/AUK-18-7.1 ]
2022-04-29 NIH pond, Bethesda, MD
Sitting on our perennial candytuft border (Iberis sempervirens) this fly is anticipating the inaugural loading of our new rotating compost barrel (this year's Earthday present from Tanya).
2022-04-29 Bethesda, MD
A metallic green sweat bee on Philadelphia fleabane, so named because they lick salt from cattle and people (though they've always ignored me). Spiking your plants with sodium can double the number of pollinator visitors.[1] They are common in our garden but small (7 mm) so you have to look for them. Some species are gold, or black or striped. I once saw a bright blue one but didn't get a picture. Unlike honey bees with a hive and a single queen who lays all the eggs, these bees are semi-social,* nesting in underground burrows** with several of their sisters, each raising their own family.
[1] Finkelstein, Carrie J., et al. "Sodium-enriched floral nectar increases pollinator visitation rate and diversity." Biology Letters 18.3 (2022): 20220016. DOI:0.1098/rsbl.2022.0016
* some species are solitary
** some species nest in decaying wood
A spring perennial, Packera aurea gives the early bee some nectar. At 7 AM the stems are still showing a bit of late spring frost. It is a shade tolerant ground cover, so the forest along the Potomac rings in the new season with a burst of yellow. Bonus: the deer don't like the Pyrrolizidine in the leaves.
2022-04-29 Cabin John Park, Bethesda, MD
A red fox on a cold morning at the end of April. Native to the northern hemisphere it still makes the list of the 100 worst invasive species because of its effects on the Australian ecosystem. We have one that comes to our garden from time to time, keeping the rabbit population in check.
2022-04-29 Cabin John Park, Bethesda, MD
It's called "Crane's bills" because of the shape of the seeds, but I don't know about the "Dove's foot". The Latin Germanium molle is easier. Introduced from the Mediterranean, it is used as an anti-cancer agent in Portugal. One study shows that it inhibits cancer cell lines in vitro at slightly lower doses than those required to "inhibit" pig's liver.
2022-04-24 McKee-Beshers WMA, Poolesville, MD
Similar to carpenter bees, carpenter ants do not digest wood, but only bore into it for nesting (the eggs need moisture, so if your house is well maintained it is safe). Carpenter ants have a symbiotic bacteria (Blochmannia), which provides amino acids that the ant can't make itself. What's especially interesting is that this bacteria is transferred from mother to child through the egg. With an intricate genetic dance,[1] sometimes with the ant genome in control and sometimes the bacteria, eventually depositing the bacteria inside the cells of the midgut and the ovaries.
2022-08-27 Bethesda, MD
[1] How Two Became One: Origins of a Mysterious Symbiosis Found | Quanta Magazine
Visiting our garden rocket for a pick-me-up before boring more holes in our fence. They don't actually digest cellulose, but instead leave little piles of sawdust on the ground. I feel a little bad that they are raising babies in treated wood, but the population seems to be doing well. Females do the boring while males fly around patrolling territory. That's a little weird since only the females have stingers.
2022-04-12 Bethesda, MD
Flight of fancy: With a bit of a boost maybe I can soar through the clouds if I flap fast enough. More likely it's just a traffic jam on the log (a log jam?) with the painted turtle trying to get past the red-bellied cooter only to find itself high-centred.
2022-08-27 Gunner's Lake, Germantown, MD
This is perhaps a seed from a milkweed variety that was being carried along on a gentle spring breeze. It must have overwintered in a pod to be in such good shape in April.
2020-04-02 Bethesda, MD
A lady damselfly, but nothing to indicate fragility. She is a carnivore who can take down insects her own size.
2022-04-22 McKee-Beshers WMA, Poolesville, MD
Site supervisor checking out the build quality.
2022-04-24 McKee-Beshers WMA, Poolesville, MD
This guy was taking a bit of a break from nest building, checking that it was comfy. This is another species which builds its nests out of lichen, plant fiber and spider webs, though placing them on top of the branch rather than forming a hanging basket like the white-eyed vireos. Just because you build a nice home that doesn't mean it is safe. One study found a 2/3 nest failure rate, with cowbird parasitism in more than half the nests.
2022-04-24 McKee-Beshers WMA, Poolesville, MD
In spring the guys hang out in the brush and trees at the edge of the field maintaining their territory, dueling with song. They share in the labour of constructing the nest, starting with spider silk and filling in with grass, leaves, twigs and moss. Although they build them off the ground between 5' and 25' they still lose a third of their nests to predation, mostly snakes and cowbirds.[1]
2022-04-24 McKee-Beshers WMA, Poolesville, MD
[1] Conkling, Tara J. Analysis of the black-capped vireo and white-eyed vireo nest predator assemblages. Diss. Texas A & M University, 2011.
Lamium purpureum only looks like a nettle but it has no sting, hence the name "deadnettle". It is a traditional Eurasian medicinal herb, with significant activity against induced paw swelling and pain (poor rats!)[1] It's also good for spring salads.
2022-04-22 C&O Canal Lock 7, Potomac MD
[1] DOI:10.1016/j.jep.2008.04.001
Probably Tribe Chironomini, but it's difficult to tell from photos. Male midges have feathered antennae which act as "ears" specifically tuned to the frequency of female wings. Hit a tuning fork at that frequency and the guys swarm in.
2022-04-22 C&O Canal Lock 7, Potomac, MD
[1] https://asknature.org/strategy/antennae-sense-vibrations
On the topic of sex differences, the female American toad (Anaxyrus americanus) is much bigger than the male.
2022-04-13 NIH Pond, Bethesda, MD
Sex is complicated. Antennaria howellii is said to be a hybrid of up to four parent species, keeping multiple sets of chromosomes so it can interbreed with all of them. Such a "polyploid complex" allows genetic exchange between species that are otherwise unable to interbreed. They are usually found as large groups of females that reproduce asexually but this one is male (he has the "antennae" sticking out of his flowers which gives the genus its name). I do hope we have some females so they can spread but I'll have to wait until next spring to find out.
2022-04-13 Bethesda, MD
Claytonia virginica shows a lot of colour variation despite a strong pollinator preference for lighter colours.[1] The defensive flavonoids quercetin and kaempferol protect the plant from slugs and rust, but also give it colours from mauve to crimson. More pollinators means more seeds but more predators means fewer seeds, and on balance colour is free to vary.
2022-04-09 NIH pond, Bethesda, MD
[1] Frey, Frank M. "Opposing natural selection from herbivores and pathogens may maintain floral‐color variation in Claytonia virginica (Portulacaceae)." Evolution 58.11 (2004): 2426-2437.
An aphid eater (Complex Eupeodes americanus) visiting an autumn cherry in full flower this spring. Each larva can consume ~2000 aphids in a week, then 3-4 weeks as an adult before the cycle begins again. You need to have flowers on hand with nectar to power the egg production. C$75/tray from a Quebec supplier.
2022-03-21 NIH pond, Bethesda, MD [DSC03822]