Dragonfly Laying Eggs

Whether it's odonates (e.g. dragonflies and damselflies) or birds, it's sometimes difficult to differentiate immature males from females. But sometimes the difference is obvious, like when I see a female laying eggs. Here's a female Blue Dasher who's doing exactly that. Many dragonfly females will hover over the water, quickly dipping the end of her abdomen (her ovipositor) down into the water and depositing an egg there. 

This is 1 of the 2 main ways that dragonflies lay eggs. Another technique is to cut a slit in a water plant and lay eggs inside the plant; I've never actually witnessed this technique.

You might be wondering why a flying insect lays eggs in water. This is because, despite adults being fierce aerial predators, as nymphs (call naiads) they lead totally different lives; they are fierce aquatic predators. 😄 When I say this, they are fierce aquatic predators in the world of the small; they aren't taking down adult turtles, herons, or (most) fish but are mostly preying on small invertebrates. (Some of the largest naiads may attack tadpoles and very small fish.)

Here are pictures of a dragonfly depositing her eggs in water.
July 15, 2022 at the Sourland Mountain Preserve
Photo 221320897, (c) jpviolette, some rights reserved (CC BY-NC)

July 15, 2022 at the Sourland Mountain Preserve
Photo 221320905, (c) jpviolette, some rights reserved (CC BY-NC)

July 15, 2022 at the Sourland Mountain Preserve
Photo 221320929, (c) jpviolette, some rights reserved (CC BY-NC)


Comments

Post a Comment

Popular posts from this blog

Northern Watersnake

Image
This April I went to Great Swamp National Wildlife Refuge with the hope (among other hopes) of seeing the Northern Watersnakes during mating season. There were 2 problems with this: I think it was slightly late in the season for this. The boardwalk trail where I had seen them in the past was partially closed due to repairs. So although I didn't see any of the 2+ intertwined snakes that I'd seen in the past, but there were still Northern Watersnakes warming themselves in the sun: April 13, 2023 at Great Swamp Photo 272117862, (c) jpviolette, some rights reserved (CC BY-NC) And here's another one coming out of the water. April 13, 2023 at Great Swamp Photo 272119139, (c) jpviolette, some rights reserved (CC BY-NC)
Read more

Female Brown-headed Cowbird

Image
Like quite a few birds, this bird is easier to identify when spotted with her significant other ; she's a Brown-headed Cowbird . Due to their tendency to be monogamous plus plain old birds-of-a-feather behavior, I usually see them with prominently brown-headed males around, greatly improving my confidence in IDing them. My understanding is that Brown-headed Cowbirds are the only obligate brood parasites in my area. Obligate brood parasites have essentially lost all their parenting skills, and thus if they were ever unable to fool other birds into raising their young, they would (almost certainly) go extinct [1]. There are, however, other brood parasites in New Jersey. These are called facultative brood parasites, and these birds will usually raise their own offspring, but will also engage in brood parasitism. (Exactly when birds perform facultative brood parasitism seems variable; one source said it occurred when resources were scarce while another said it occurred when resource
Read more

Rooftop Turkey Vultures

Image
I met these Turkey Vultures by just walking out of my apartment. (I theoretically could have gotten a picture without going outside, but that extra layer of glass can degrade picture quality a little.) Although they don't show up on these rooftops daily, they're not an uncommon visitor to my apartment complex. Similar to this spot of the woods , I wouldn't expect this to be a great place to find carcasses. I'm thinking they're here mostly because: They don't have to worry much about predators up there. They get a pretty good view of the area in case something should happen to succumb. (This apartment was near the top of a hill, providing a better view than most of the other apartments.) Since this picture was from February, it's probably a slightly warmer spot, especially near those furnace vent pipes. Although these are Turkey Vultures, it's also not unusual to see Black Vultures up there too. February 28, 2023 at Finderne Photo 264703396, (c) jpviole
Read more