Springtime with awesome, beautiful and awe-inspiring insects

This spring of 2021 has offered some delightful chances to see interesting insect species, some of which I’ve noticed before and some that were new or gave me my first opportunity to observe them up close. While not many people aside from entomologists pay much attention to the “creepy crawlies,” they are certainly well worth watching in my view. Including insects in my nature observations greatly enhances my experience of appreciating the natural world.

male giant ichneumon wasp P5068000© Maria de Bruyn res (4)

ichneumon wasp P5067996© Maria de Bruyn res (2)

female giant ichneumon wasp P5068007 © Maria de Bruyn res (2)The month of May brought me two especially awe-inspiring events. The first was seeing long-tailed giant ichneumon wasps (Megarhyssa macrurus) preparing for reproduction on a nature trail in Chatham County. It was easy to distinguish the females (right) from the males (above) because they had very long ovipositors (a tubular organ through which a female insect lays stored eggs). In the species I saw, the ovipositor can be 4 inches long!’

female giant ichneumon wasp P5068028© Maria de Bruyn res (2)

There were several male and three female wasps flying about. None of them showed the slightest interest in the large human looming overhead. Even if they had, I needn’t have worried since these wasps don’t sting people. The females were busy pressing their antennae against a disintegrating hardwood log’s bark, aiming to detect vibrations inside.

ichneumon wasp P5068180© Maria de Bruyn res (2)

The mothers-to-be were “listening” for the best spots to lay their eggs by identifying where the larvae of the pigeon tremex horntail wasp (Tremex columba) were buried. Why you ask? The mother ichneumon paralyzes a horntail larva before laying an egg next to it. When her own offspring emerge from the eggs, they will eat those unfortunate horntail larvae while they prepare to overwinter until they emerge as full-grown ichneumon wasps in the spring.

ichneumon wasp P5068058 © Maria de Bruyn res (2)

 

The giant ichneumon’s ovipositor has three components. In the middle is the ovipositor proper, a filament with two interlocking parts that slide against one another; it is tipped with a cutting edge that can drill through wood. Some researchers have data indicating that the cutting edge may contain some ionized zinc or manganese.

ichneumon wasp P5068164© Maria de Bruyn res (2)

Two other thin filaments called valvulae sheath the central structure and their function is to protect the egg-laying organ. During egg-laying, they arc away from the ovipositor.

ichneumon wasp P5068171© Maria de Bruyn res (2)

While I watched one female wasp in particular, she sometimes had part of her ovipositor coiled up in a transparent expandable pouch at the end of her abdomen.

ichneumon wasp IMG_2003© Maria de Bruyn res (2) ichneumon wasp IMG_2002 © Maria de Bruyn res (2)

She would push out the ovipositor and appeared to smooth it out with her legs. The literature I read about the wasps did not explain this movement, but I thought she might be pushing eggs down the tube. Watch the video to see what you think! 

When she finished this smoothing movement and had found the right spots for her offspring, the protective lining filaments separated from the ovipositor itself and she inserted it into the log. It was a fascinating process to witness.

 

female giant ichneumon wasp P5068170 © Maria de Bruyn res (2)

female giant ichneumon wasp P5068109 (© Maria de Bruyn res (2)

Although ichneumon wasps are parasitic, various species are beneficial insects since their larvae feed on insects that harm food crops such as boll weevils, codling moths and asparagus beetles. The adults usually only live about 27 days and may only drink during that time. Their adult goal is to find a mate and then reproduce.

ichneumon wasp P5068014 © Maria de Bruyn res (2)

Another way in which the ichneumon wasps have contributed to human society is by serving as an example for the medical community. The STING Project at the Imperial College in London is investigating options for Minimally Invasive Surgery (MIS) to diagnose and treat various medical pathologies. The research team is now developing a flexible steerable probe that was inspired by the ichneumon wasp’s ovipositor!

cecropia moth IMG_0019 © Maria de Bruyn (2)My other exciting insect event involved a moth. Last fall, a cecropia moth (Hyalophora cecropia) positioned its cocoon on the door jamb of the women’s restroom at Cane Creek Reservoir. The reservoir’s manager feared that it would be damaged there and asked if I would be willing to care for it over the winter. I took the cocoon home and kept it safe during the fall, winter and much of this spring.

Cecropia moth larvae (caterpillars) are often found on maple, cherry and birch trees. Why this one chose a building as an overwintering site is a bit of a mystery. Since the pupa was going to be dormant all winter, I placed it upright in a large plastic container with a grate over the top and kept it on my screened-in porch.

cecropia moth IMG_0020© Maria de Bruyn (2)Periodically, I would check on it and it seemed to be ok. This was important as these moths are “univoltine” — they only have one generation of offspring per year. Out in nature, the caterpillars may fall victim to parasitic wasps and flies that lay their eggs on them. So it was fortunate that we were able to “rescue” this cocoon.

One evening at the end of May, I stopped working on my porch to go inside to watch the news. When I came back after about 20 minutes, I spotted a brilliant large moth on the screen. My youngest cat spotted it at the same time, so I shooed her inside. The cocoon scarcely had a hole in it; I really wish I’d seen how the huge moth got out.

cecropia moth IMG_0006© Maria de Bruyn (2) res

cecropia moth IMG_0003© Maria de Bruyn 2 res

The cecropia moth is North America’s largest moth with a wingspan up to 7 inches. The males and females look similar but the males like this one have larger, more feathery antennae.

cecropia moth IMG_0012© Maria de Bruyn (2) res

Female moths emit pheromones that the males can detect from up to a mile away. After mating, the female lays up to 100 eggs. Both sexes die after about two weeks as they lack functioning mouths and digestive systems and don’t eat.

cecropia moth IMG_0014 © Maria de Bruyn (2) res

 

The moth’s short adult lifespan must have made this guy anxious to get underway. Or seeing my cat and I hastened his development. One website reported that it takes the moth a few hours to dry before they can open their wings and fly.

cecropia moth IMG_0011© Maria de Bruyn (2) res

 

However, very soon (perhaps 10 minutes) after I removed him from my porch and took him outside (never touching him with my hands), he began vibrating his wings. In less than a minute, he launched himself upwards and flew towards the top of the nearby tall pine trees, setting off on his quest for a mate.

cecropia moth IMG_0016© Maria de Bruyn (2a) res

I suppose it is possible that the moth had emerged earlier and had crawled away to hide but that seemed unlikely. In any event, he looked like he could fly just fine, and I sincerely hope that he found a mate and that they were able to collaborate in ensuring a new generation of this stunningly beautiful species! And I was grateful for having agreed to overwinter the cocoon as it enabled me to contribute to the propagation of this wonderful moth. In any event, I was enthralled to see what a gorgeous creature he was. These moths are generally nocturnal so seeing him was a treat!

cecropia moth IMG_0017 © Maria de Bruyn (2) res

, , , , , ,

A star performance!

 

Who is this above? Read on below for a few looks at a usually highly elusive bird.

But first, let me say that in the Piedmont region of North Carolina (NC) spring is an especially nice season with abundant flowers and many birds filling the air with lovely courtship calls and songs. Sometimes, you get a little confused when walking in a reserve — thinking there are several species of birds in the vicinity to judge by all the different vocalizations, but then you discover you are hearing a concert by one of the avian mimics — Northern mockingbirds, brown thrashers and gray catbirds are both talented imitators of other birds’ calls.

While the mockingbirds repeat other birds’ notes three times each, brown thrashers (Toxostoma rufum) sing out two repetitions of other species’ songs, interspersed with a large variety of their own calls. A thrasher has been serenading lately near one of a local nature reserves’ ponds. On this occasion, s/he had an Eastern towhee audience (Pipilo erythrophthalmus).

       

A bird that does not have a lovely call, the American bittern (Botaurus lentiginosus), sometimes sounds a bit like a bull bellowing, which led to one of its nicknames — “thunder pumper.” Despite its lack of melodious calls and songs, however, birders get excited when one is spotted because this medium-sized heron (2-3 feet tall) usually is only visible hiding among dense grasses and reeds. In contrast to great blue herons or great egrets, American bitterns lead mainly solitary lives, so birders can’t count on seeing a group of them either.

One local nature reserve became a real hot spot recently when a local birder alerted other bird lovers to the presence of a bittern at one of the ponds. Unexpectedly, this bittern was not shy at all.

 

Even when s/he was being watched by half a dozen people, the bird emerged from the grasses and reeds to forage for food at the water’s edge or stopped for a grooming session in front of an audience. And this went on for over a week as the bird gave us a star performance.

 

 

When approached, the bittern’s usual “concealment” pose is to stand tall with its neck stretched upward and its bill pointing at the sky. They don’t move until they feel it is safe to resume stalking their food.

           

When they stand this way, some people say they look like they have “googly eyes”. The bitterns can focus downwards even when pointing their heads upward; it is surmised that this ability helps them spot and catch the creatures on which they feed.

   

I can see where the googly-eyes terminology was applied to them, but I recently saw a common grackle (Quiscalus quiscula) that had much more of that look in my opinion!

In one of their typical hunting modes, bitterns bend over and stand almost motionless, slowly lowering their long bills down so that they can plunge their heads quickly into water to grab their prey, which they bite or shake to death.

 

When they lift their heads, you may notice their third eyelid in position, indicating that they shielded their eyes while submerged. They also engage the nictitating membrane when they scratch their heads, getting close to their eyes – the bittern’s very large feet make that a very good decision on their part!

   

After catching their prey, the bittern subsequently repositions its prey — a tadpole, crayfish, frog, snake, rodent, fish — inside its bill so that it can be swallowed head first. Parts of the eaten animal that they can’t digest are later regurgitated as a pellet.

 

American bitterns are considered a species of high concern by Waterbird Conservation of the Americas. It is the loss of wetlands habitat that is contributing to their decline; in the last decades more than half of the original wetlands in North America have been destroyed or degraded. Let this past Earth Day be a reminder of the very urgent need to make haste in protecting the natural areas that remain and restoring areas that can be rescued.

 

Wandering a flooded forest

The year 2020 ended up being the wettest year on record since 1944 in the Piedmont region of North Carolina, but the rains didn’t end in December. In fact, the area recorded its second wettest February on record in 2021 and it was noticeable in the amount of flooding we saw.

Whereas Jordan Lake at full pool (normal level of the reservoir) is 216 feet above sea level, the level rose to 230.3 feet on 23 February 2021 – the day that I unknowingly chose to go for a walk in the forest bordering the lake.

 

I didn’t notice the flooding immediately as I first walked through a meadow area to get to my usual walking site. What immediately drew my attention was the amount of canine scat on and alongside paths.

With a lack of human visitors, the foxes, coyotes and other animals obviously felt more comfortable wandering everywhere throughout the reserve.

Lots of flies were buzzing around the remaining dried flower stalks and I spied an early leafhopper – the first time I had seen a lateral-lined sharpshooter (Cuerna costalis).

Setting off into an area where I often saw woodpeckers, I discovered my usual walking trails had disappeared under an expanded lake.

 

A sweet Carolina wren (Thryothorus ludovicianus) hopped into view, apparently wondering why a human being was again being seen in these parts.

 

 

I discovered it was a good idea, too, to watch where I was walking because the remaining forest floor was alive with thin-legged wolf spiders (Pardosa) crawling over the fallen leaves.

 

I wonder if there were so many in this area as they had all fled the rising waters to congregate in the same area. (Certainly a way to meet other spiders!)

Wandering further, I saw that I couldn’t get anywhere close the shoreline that used to be a favorite birding area.

 

The osprey nest, not yet occupied, is normally on a land-bound snag but now it was in the water.

There were still some birds around, but not as many as I was used to seeing. Off in the far distance, a ring-billed gull (Larus delawarensis) was fishing.

Never had I seen this lake’s water so high – many of the areas where I usually walk were completely submerged.

I walked along the new lake edges and noted lots of tufted titmice (Baeolophus bicolor) exploring the waterlogged fallen logs.

 

 

The Eastern bluebirds (Sialia sialis) were also flying down from tree trunks and branches to see what was near the water.

On the branches above, a a yellow-rumped warbler (Setophaga coronata) stopped by and a pine warbler (Setophaga pinus) showed off his beautiful yellow plumage.

   

To my delight, a pair of brown creepers (Certhia americana) were ascending the water-bound trees searching for meals.

     

I find these birds beautiful and admire how well they blend in with their hunting grounds.

For me, the brown creepers have some of the best camouflage abilities around.

Overhead a red-tailed hawk (Buteo jamaicensis) flew by surveying the expanded water boundaries and I detected a Chinese mantis egg case swaying atop a shrub.

Because my walking area had been greatly reduced, I decided to leave after gazing into one more area where I usually wandered. To my surprise, I saw a wood duck (Aix sponsa, right) and a pied-billed grebe (Podilymbus podiceps) swimming over what is usually a leaf- and vegetative-laden forest floor. Perhaps they enjoyed visiting a new, albeit temporary, swimming area.

I do think that some wildlife may have suffered. This polyphemous moth cocoon (Antheraea polyphemus), which I had photographed in another part of the forest bordering the lake, was eventually submerged for some days under about four feet of water. When the area again reappeared, I found the cocoon and it was still intact but only about half its original size, so I think the moth was doomed. Now that the lake levels have fallen further, it will be interesting to see how the forest is recovering after having been submerged.

 

Red-winged, rusty and ravishing – black bird delights!

   

Two species of birds that I enjoy seeing during the autumn and winter months in North Carolina (NC) are red-winged blackbirds (Agelaius phoeniceus, above left) and rusty blackbirds (Euphagus carolinus, above right). Both species breed in the northern USA and Canada, traveling to the southern USA during the colder months.

There is also a population of red-winged blackbirds that nest in NC’s Piedmont region. I’ve seen them collecting nesting material at local ponds and wetlands but have never had the pleasure of seeing their nests or watching them feed their young.

The red-winged blackbirds have two avian records to their name: 1) currently perhaps the most numerous land bird in North America, with counts of more than 1 million birds in a flock!! and 2) one of the most researched wild bird species anywhere.

The male red-wings call the attention of females with the red and yellow patches on their wings. It turns out that those with larger patches are more successful in disputes with other males for territory and mates.

     

Some males have been recorded as having up to 15 mates in their territories during a season, but it turned out that 24-50% of the nestlings had another male as a parent!

 

The females look very different from the males with beautiful reddish-brown striping. Their faces are marked by off-white eyebrows.

 

 

They often nest near other red-wings.

             

Doing so means that their nesting area has multiple parents on the alert for predators.

It is interesting that Native American languages also had common names that describe their physical characteristics (red patch, spotted, marked). The longest one that I read about was “memiskondinimaanganeshiinh” (Ojibwa meaning “a bird with a very red damn-little shoulder blade”)!

 

 

During breeding season, the male rusty blackbirds have glossy black plumage with a greenish sheen. At other times, they have rusty tips to their feathers, giving them a mottled look.

The females may also look a bit mottled but have much more light brown and beige coloration.

 

In contrast to the numerous red-winged blackbirds, the rusty blackbirds used to have high numbers but have lost up to 85-99% of their populations during the past 40 years for unknown reasons.

 

The sharp decline is so mystifying that scientists have formed an International Rusty Blackbird Working Group to investigate what is happening.

   

 

One possible explanation is a decline in wetlands, especially in the Southeastern USA where 80% of the birds overwinter. A resurgence in beaver ponds may be helping them, which shows how protecting one wildlife species can also assist another one. I have indeed seen them in areas where beavers have been active.

 

The rusty blackbirds that I spotted were indeed using local wetlands in their search for food, turning over the sodden leaves with their feet and beaks as they searched for sustenance.

The International Working Group is asking people to report their sightings of these birds to eBird to help track the species.

To close this blog, I wanted to share just a few photos of some other birds who are a beautiful black color: my faithful American crow couple (Corvus brachyrhynchos).

They have been visiting with one of their offspring from last year, just as they have done in previous years.

 

 

Unfortunately, it appears that one of the birds has somehow suffered an injury to one leg and foot. S/he has been hopping around on the ground and can fly well, but it is a mystery as to what happened to hurt this large bird. Perhaps a tussle with one of the neighborhood hawks?

 

 

 

 

Spring weather is beginning in our area, which means some avian species will be leaving us and some new ones will be arriving or passing through in the coming weeks. The next blog will feature a few of our feathered friends who will be leaving.

Wrestling with your food – not for me!

Our 2021 winter weather in central North Carolina has been one of the wettest on record so far and is set to top the list by the end of the month. But occasionally we have had some sunny, albeit cold, days to everyone’s delight. On one recent walk on an unusually sunny day, I saw a beautiful little syrphid fly flitting about the forest floor and caught a fleeting glimpse of an Eastern rabbit, but that has been it for non-avian species except for the deer, squirrels and chipmunks in my yard. So my focus has continued to be on the more bountiful birds.

On successive visits to a pond in a neighboring town, mostly to watch the hooded mergansers, it was noteworthy to see that a single ring-billed gull (Larus delawarensis) had taken up residence. S/he spent a lot of time atop one of the parking lot streetlights at the pond’s edge. It gave a perch for a good overview of the water and its residents.

The bird is usually alone when I see him/her. They are sociable birds, however, and it’s interesting that, in some cases, two females will share nests and raise their two broods together.

 

I’d seen her/him catch fish there before and noted that the bird never just alighted, positioned the fish and swallowed it quickly. Perhaps this is because it has a broad diet and has learned to eat its varied foods differently.

Not only do they devour fish, insects, earthworms, rodents and grain; they also will scavenge people’s food if they can get to it, for example, on a beach or in a fast-food parking lot.

This yellow-legged gull will fly around the pond from time to time, looking quite beautiful in flight.

  

S/he doesn’t go fast, although they can reach speeds of up to 40 mph. Rather this bird soars quietly in circles scanning both the water and its surroundings.

Recently, I watched this gull catch a fish and then take a long time to actually eat it. First, the bird spent some time positioning the fish just right in its beak.

Then it began dunking the fish underwater and slapping it on the water as well.

Was it trying to kill the fish before consuming it?

After doing this for a while, the gull suddenly picked up the fish, flew up into the air and dropped it in the water.

Next, it turned tail and dove head-first into the pond, likely hitting, stunning and perhaps drowning the fish with this maneuver.

A Cornell University website says that adult ring-bills “play” by dropping objects and then catching them mid-air, perhaps as a way to practice their hunting technique. But in this case, that didn’t seem to be the case.

The gull still didn’t eat the prey right away, however.

S/he kept hitting the fish and moving the aquatic meal around in its mouth.

A couple times it looked like the fish was positioned just right for swallowing.

And then, the re-positioning continued.

Finally, after some time, it looked like the bird had finally ingested the meal and s/he took off again.

It was an interesting observation of animal behavior – my favorite way of spending time on nature walks. And it will likely remain a bit of a mystery as to what the ring-bill gull’s intentions were in carrying out these moves. 😊