In the spring of 2021, I finally put up a couple of nest boxes in the yard of the new house. Both boxes were built and gifted by my father, Bart Duncan. Much appreciation! One box was designed specifically for bluebirds and a pair quickly staked their claim. They had an initial successful clutch, fledging three chicks, but on the next attempt, tragedy struck. During my monitoring visit, where there had been four half-developed chicks the day before I found not a single one. I believe the neighborhood racoons made a meal of them sometime during the night, leaving no evidence. It was early enough in the year that I wasn’t surprised that the pair tried again, but what surprised me was that they did not build a nest in the bluebird box, but used a box that was designed for Carolina Wrens that was bolted to the side of our screen porch. It made for some great photo opportunities that I am sharing here. I learned from my mistakes and have installed a baffle around the pole to the bluebird box along with a wire cage over the nest entrance. If a brood predator wants to get at them now they will really have to try hard. I am happy to say that to date, in the 2022 season, the pair successfully fledged two clutches – one of six and one of five chicks. Eleven new bluebirds this year, flooding the subdivision with bluebirds!
Anyone who has hung around biologists and naturalists long enough has surely heard the complaints of how taxonomists are going too far in their evil over-splitting ways. Their notion being that phylogenies painstakingly developed via decades of phenotypic comparisons should not be overturned by a few afternoons of running gels in a lab. I’m sure most of us can point to a convincing example of over-splitting amongst our favorite groups of organisms, but I hope that the subject that I am featuring tonight will give you pause before reaching for that familiar defense and realize there are circumstances where a group benefits from a fine dissection when the appropriate tools are available.
A great example of a group that has benefited from a well-executed genetic taxonomic treatment is the Spiranthes cernua species complex of the “ladies tresses” orchids. This species complex has long been known for cryptic species with curious cases of plants being plants – exhibiting hybridism, polyploidy (having more than two sets of chromosomes) and apomixis (reproduction without fertilization). The species, Spiranthes cernua, which is found in Missouri, has been problematic and considered as a polyphyletic taxa (derived from two or more distinct ancestral taxa). In attempting to shed light on the phylogenetics of this species complex, Mathew Pace and Kenneth Cameron have published a fantastic treatment in which they attempt at “Untangling the Gordian Knot”. Most of what I write here is paraphrased from their paper cited at the end of this post.
A common method of speciation in plants is interspecific hybridization. Pace and Cameron identified three instances of ancient hybrid speciation involving S. cernua. One of these circumstances that has now been given specific status is Spiranthes niklasii. This species is near-endemic to the Ouachita Mountains of Arkansas and is likely a result of a proposed ancient hybridization event between Spiranthes cernua and Spiranthes ovalis.
Pace and Cameron describe S. niklasii as being quite similar in appearance to S. cernua, but can be distinguished by “a central ridge of small papillae on the adaxial surface of the labellum, more strongly campanulate flowers, and usual preference for a more xeric habitat.” When I read this and found out we had an opportunity to see this species, I knew I wanted to try and capture those papillae in a photograph. We found this species in bloom in Saline and Pulaski Counties in Arkansas on 10, October, 2021. While my photos cannot do justice to the excellent figures found in the above mentioned work, I was still thrilled to be able to capture these minute structures while on a camping trip in the Ouachitas.
By the way, one of the other cases of hybrid speciation involving S. cernua that was identified by Pace and Cameron has further implications on my work. Spiranthes incurva is a newly described species that is hypothesized to be the result of an ancient hybridization between Spiranthes cernua and Spiranthes magnicamporum. In Missouri, the result of this split is that S. incurva now lies roughly above the Missouri River while S. cernua is found south of the river. This means that I now have added another species to my orchids of Missouri. A new orchid for me to photograph!
I would like to thank Casey Galvin and Eric Hunt for helping me find these plants.
Pace, Mathew C., and Cameron, Kenneth M. 2017. The systematics of Spiranthes cernua species complex (Orchidaceae): Untangling the Gordian Knot. Systematic Botany. 42(4): pp. 1-30
One day I would love to know how many of our moths received their common names. So many of them are interesting and perfect, like this, the sweetheart underwing (Catocala amatrix). In this case, the Latin binomial agrees. Catocala referring to the namesake, hidden underwing and amatrix meaning lover.
This moth was found in Franklin County, MO.
I’m never really fortunate enough to get a good image with their hindwings exposed, but here is a glimpse of the beauty they keep hidden, apparently useful for startling would-be predators upon their taking flight.
We found this cocoon of a parasitoid wasp (Ichneumonidae) during a WGNSS Nature Photo Group Outing in September of last year. This distinctive cocoon is identified to belong to a member of the subfamily Campopleginae who are characterized as koinobiont (allows host to continue development) endoparasitoids that primarily parasitize lepidopteran hosts. We did not find any remains of a potential host nearby.
The lemmings in the sub-arctic and arctic regions of Canada and Alaska must of had a bumper year in 2021 because the mid-west United States had an irruption 2021/2022 winter season for the Rough-legged Hawk (RLHA). Lemmings are the primary food source for this beautiful species during its summer nesting cycle. Typically, during our winters, RLHA are found in ones or twos in Missouri, south to the Missouri River. Around the St. Louis area we may only see one or two birds in a typical winter. This season was quite exceptional. Looking at the occurrences for this past season documented in eBird shows this species has been seen across the state, up and down the Mississippi River, even as far south as the Arkansas border. On a birding day in February, Miguel, Dave and I counted eight as we moved along the Hwy 79 corridor.
On an early mid-February morning Miguel and I hit one of our favorite winter birding locations in St. Charles County to see what luck we could have. We knew a RLHA or two had been reported and photographed by multiple folks and we had our hopes high. Nothing much was showing up on this frigid morning but I thought to check a specific area that was off the beaten path and had a history of holding birds that wanted to get away from the busy roads and throngs of gawkers. That is when we ran into an individual RLHA of our dreams. We wound up spending hours with this cooperative bird despite freezing fingers, toes and tips of our noses. We simply stood outside our vehicles and watched as the bird perched, hover-hunted, soared and fed, all the while seeming oblivious to our presence. The following video and images are the results of this day.
The three images above show the bird hover-hunting. This process can be seen in the video as well. The RLHA will hunt by the more typical buteo standard of sitting on a perch and waiting for the right opportunity to show itself. However, because they spend roughly half of their lives in or around the tundra biome where there are few trees or other tall perches to do so, they have developed this method of hunting that allows them to stay high above their prey. They will often start very high, using their keen eyesight to spot the motion of a rodent. They will then descend in tier-like steps, getting closer to their eventual target until finally making their catch. It is quite a sight to watch a buteo of this size hover-hunting and something I doubt I could ever get tired of watching. I think these images show some modifications that help them in hover-hunting. Their wings are longer and narrower than most buteos and their tails are longer and broader as well. With these tools they can keep their heads nearly completely stationary in the sky for minutes at a time.
How I would love to see them in their nesting range some day! These birds typically nest on rocky cliffs and because there is often a lack of sticks and branches available in the tundra, they will often use caribou bones to build their nests. They line their nests with soft vegetation like moss and lichen as well as the fur and feathers of their prey.
Because they are so-well adapted to living on the wing, in more open and treeless areas, the RLHA will outcompete species like Red-tailed Hawk and Ferruginous Hawk that prefer to hunt from tall perches. If you have spent enough time in the field, you have probably watched Red-tailed Hawks attempting to hover-hunt when the winds are just right. However, they cannot keep this activity up for very long and do not do it nearly as well as RLHA.
I hope this post gives a good glimpse into the winter life of the Rough-legged Hawk and why, when asked what is my favorite bird species, this is one out of ten or so that I would give as the answer.