Reader Jacques Hausser, a professor of ecology and evolution at the University of Lausanne, sent some bizarre caterpillars (fake one: they aren’t lepidopteran larvae but the larvae of hymenopterans) doing some coordinated nomming:
Last monday I met these false caterpillars eating poplar leaves. They are the larvae of Craesus septentrionalis, the birch sawfly, a remote parent of wasps and honeybees. You can tell them apart from the real caterpillars of butterflies and moths by their 6 yellow pairs of “prolegs” or false legs following the usual 3 pairs of insect legs. Real caterpillars have only 5 pairs of prolegs. Their strange attitude is actually a reaction to disturbance: they expose their abdomen where a special gland produces a repellent substance. I find their disciplined way of feasting collectively, following each other along the (remaining) edge of the leave, rather amazing.
From Stephen Barnard: “Red-tailed hawks ( Buteo jamaicensis) warming up in the morning sun”:
There’s the red tail!
Nice. Stephen: Love the red tail shot of the Red Tailed Hawk. Looks like they are showing off.
I thought the same – “see, this is my tail. Isn’t it lovely?”
Terrific photos!
The leaf edged by false caterpillars could inspire a ceramicist to design a lookalike trivet. I would use it! 🙂
The first two photos are of a juvenile and the third is of an adult.
Those false caterpillars are trippy. They almost look fractal.
Beautiful Stephen!!
Great pictures but, technically speaking, a modern sawfly species cannot be a “remote PARENT” of wasps and honeybees. I know what the writer intends, but it is important to avoid any semblance of the ladder-like view of evolution that is still prevalent in the general public.
Sorry – I’m not a native english speaker (well, I’m not an english speaker). In french, parent (singular) usually means “relative”, specially when used with “remote”, and never “ancestor”. Parents (plural) is used (not exclusively) for mother-and-father.
William the Conqueror would not have invaded England, I would not make this kind of mistakes…
I love the way the caterpillars take up that defensive position when disturbed – it’s really cool looking.
Stephen’s hawks are really nice! Beautiful shots!
As always, great pictures. That is one nice red tail.
Those are amazing sawfly larvae. I have seen a similar species, but nowhere near as numerous.
I expect that besides providing an amplified deterrent to predation by stinking together, they could also wind up helping each other to thwart the many parasitic flies and wasps that want to lay eggs on them. ‘Larvae, unite!’
The coordinated eating of the sawfly larvae reminded me of the Pelicans synchronized eating from yesterday’s pics. As Stephen said above they are “trippy”.
Beautiful hawk photos! I never get bored of your birds Stephen.
These hawks were basking in the sun after a cold, moist evening. The juvenile didn’t spook — just fluffed out to catch a breeze. I photographed these perched on power poles along a rural road. The hawks are accustomed to pickups and farm equipment driving by, and aren’t nearly as spooky as they would be in a more natural setting, although they are suspicious when you stop.
Also, in the first photo the hawk is perched on one foot, possibly to warm up the other. I haven’t seen that before. It was a damp, chilly morning.
I noticed that, it’s cold when you stand on one leg to warm up the other. Winter is coming!
Nearly all birds spend quite a bit of time standing on one foot, esp. when sleeping.
In fact, if you have a pet bird that sleeps on both legs, be on the lookout for illness.
AFAIK, we don’t really know the why of this behavior–preventing heat loss through bare parts might be the reason some times, but that’s not always an issue. Here’s a Trumpeter Swan–a lotta bird!–on one leg in the middle of a summer afternoon:
https://flic.kr/p/fAuGmR
One website offers the explanation that, since birds find it just as easy to stand on one leg as two, they do it simply to give the other foot a rest.
I often wonder if heat is really an issue with birds since I see them standing for ages out in the snow with their skinny little legs all the time.
Well, of course heat is an issue for them, which is why they developed the original down coats. 😀
But I know you meant the legs. This explanation from a quick Google search seems to make a lot of sense…I’m not au courant enough to know if it represents the latest thinking, but if not, someone here will probably jump in.
http://askanaturalist.com/why-don%E2%80%99t-ducks%E2%80%99-feet-freeze/
It’s sort of a head-slap moment when you get to the bit about how the leg-temp regulation system also works in warm weather. Well, duh! (After all, they can’t take their coats off! Except during molt.) Wouldn’t it be nice to be able to sunbathe while suspended in mid-air? (Not that I’ve sunbathed in years…)
Fantastic sawfly larvae pics!
We used to have mugo pines that were extremely vulnerable to sawfly attacks. These larvae would line up on the needles and really blend in. There could be quite the infestation but you could easily miss it due to this posture. But–if you waved your hand near them, they’d all simultaneously dip and roll–quite startling at first, then just fascinating.
Not my photo:
http://www.treesforlife.org.uk/images/pine%20sawfly%20larvae.jpg