Archive for ‘Nature Notes’

Brood Update

I snapped these Laughing Gull (Leucophaeus atricilla) photos a month ago at Rockport Beach. Our local beach is actually a man-made peninsula that juts into Aransas Bay, forming a protected area known as Little Bay. Much of the Little Bay side of the peninsula is closed to recreation during breeding season to allow Laughing Gulls, Black Skimmers, terns, egrets, and herons a quiet space to raise their young.

I suppose quiet may be a relative term since the raucous calls of these gulls are loud and pervasive. I caught the earlier part of nesting season back in May. If all goes well for them, in two or three years these young ones will be nesting here also.

Life Span

Note the contrast between these Four-pennant Dragonflies, (Brachymesia gravida). One appears young and healthy while the other looks old and worn. Neither one was willing to share their section of the pond. After dashing out to chase off interlopers they would return to their respective perches. Just another busy day at Aransas National Wildlife Refuge…

Ripe

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Mustang Grapes (Vitis mustangensis), Aransas National Wildlife Refuge, Tivoli, Texas July 2019

A couple months back I stumbled across some green Mustang Grapes and it made me so very curious to taste them once they ripened. Well, I finally got my wish a couple weeks back. The plump fruit was juicy and mildly sweet though the skin was quite tart. I employed a technique I learned as a kid when eating Concord grapes off the vines in our yard; I popped the entire globe in my mouth, sucked out the tender flesh, and spit out the skin (so not only were the grapes delicious, they were fun to eat, too).

Fuzzy Friends

I met these two fine young males at Aransas National Wildlife Refuge a couple weeks ago. I’m basing my super-scientific age guesstimate on the fact that they are near the end of their antler growing period and only have small racks.

In case you didn’t know, antler growth is controlled by photoperiod (length of day) and typically starts in March. Testosterone levels begin to rise in August, as the days grow shorter, which signals the end of antler growing (just in time for mating season).

Did you know that antlers are the fastest growing tissue among mammals? In just 120 days they can grow over 200 inches. That incredible spurt requires excellent nutrition which is provided by the vascular tissue (aka velvet). As the antlers harden, the velvet is shed, becoming a highly nutritious snack scavenged by all manner of wildlife.

Cartilaginous Fish Parts

Since shark skeletons are comprised of cartilage not bone, their parts aren’t that commonly found on the beach. The one exception to that rule is shark teeth, but those are made of dentin, a calcified material which is harder than bone. (Side note: The average shark goes through over 25,000 teeth in a lifetime.)

As you can see in the first photo, the cartilage is added in layers, which creates a tree-ring-like signature that can aid in assessing the shark’s age. Some researchers are even extrapolating environmental information from the isotopes captured in each ring. Nature is so cool!