Another favorite dolphin game is to ride the pressure wave at the front of a fast moving boat. Called “bow riding,” the bow wave pushes dolphins fast forward without any flapping on their part.
Dolphins like this game so much that they rushed toward the whale watch boat. Robin Agarwal says of this photo, “Pacific White-sided Dolphins and Northern Right Whale Dolphins stampeding towards the boat to bow ride – my favorite sight in the world.”
Here they are bow riding with an “unusual swirl color morph” among them.
In 1976 Jerry Kemperman and Burton Barnes discovered that 106 acres of quaking aspens (Populus tremuloides) in the Fishlake National Forest of Utah were actually all the same male plant, one root with thousands of suckers that grew into trees. It came to be known as Pando — “I spread.”
Pando weighs 6,600 tons making it the heaviest known organism on Earth and it is very old, though no one is sure whether it’s 10,000 or 80,000 or even a million years old.
However, almost as soon as Pando was discovered researchers found that sections of it were not rejuvenating because new sprouts were being overbrowsed by deer. In that part of the U.S. the species is mule deer (Odocoileus hemionus).
So they fenced it — twice — one fence in 2013, another in 2014.
Then in 2018 Paul Rogers and Darren McAvoy of Utah State University conducted a followup study sampling Pando’s health inside and outside the deer exclosure fences and concluded that the fencing was not working.
According to September 2022 Sci.News “The unfenced areas are experiencing the most rapid aspen decline, while the fenced areas are taking their own unique courses — in effect, breaking up this unique, historically uniform, forest. … Fencing alone is encouraging single-aged regeneration in a forest that has sustained itself over the centuries by varying growth.”
“One clear lesson emerges here: we cannot independently manage wildlife and forests.”
Aldo Leopold’s experience in his early career when he worked to eradicate wolves from the American West changed his perspective on trees and deer. At one point he shot an old female wolf and was there to see the green fire go out of her eyes as she died. He wrote …
I thought that because fewer wolves meant more deer, that no wolves would mean hunters’ paradise. But after seeing the green fire die, I sensed that neither the wolf nor the mountain agreed with such a view.…
I now suspect that just as a deer herd lives in mortal fear of its wolves, so does a mountain live in mortal fear of its deer. And perhaps with better cause, for while a buck pulled down by wolves can be replaced in two or three years, a range pulled down by too many deer may fail of replacement in as many decades.
Last week as I walked past a team of Allegheny Goatscape goats munching invasive plants in Schenley Park, I noticed a sign that described their sleep cycles. The goats, who are guarded by a donkey, sleep 5 hours in a 24-hour day. The donkey sleeps only 3 hours. Imagine being able to function normally on so little sleep!
Some animals sleep less than we do, some sleep more.
We humans, who average 8 hours per day, are well aware of our pets’ sleep cycles. Cats sleep 12 hours a day (so do mice!). When this man gets up his cat will curl up in the warm spot and go back to sleep.
It’s mid November and the rut is at its peak in Pennsylvania. Bucks sniff the air for females in estrous (flehmen), chase does in heat, and hide with them in thick cover to breed repeatedly. Some run into traffic, including yesterday’s road-killed 6-point buck in Schenley Park. Meanwhile birders in Frick Park are seeing all of this up close. Very close.
On 10 November Charity Kheshgi and I encountered a group of five. Two does and an 8-point buck were hiding in a thicket when a 4-point buck walked onto the trail behind us, sniffed the air and looked down at the females. Meanwhile another doe (at top) walked onto the trail ahead of us. This could have been dangerous for the two of us. Fortunately the deer did not view us as competitors.
The 8-pointer was hard to see in the underbrush but he resembled this 10-point buck Mike Fialkovich saw on 5 November that appears to be flehmening.
Deer are a prey species, alert to the presence and intent of predators. “Is the predator here? Is it hunting?” And they move to locations of least danger. We see them up close in Frick Park because they have learned that humans in Pittsburgh’s city parks are not dangerous even during hunting season.
Meanwhile, hunting is currently in progress statewide and it’s good to be aware of it. We have so many deer in our area — Wildlife Management Unit (WMU) 2B — that hunting lasts longer here than in most of the state.
Here’s a quick summary of deer hunting times and types, now through January, in WMU 2B both Antlered and Antlerless unless otherwise noted.
now – Nov. 25, including Sundays Nov. 13 and Nov. 20, WMU 2B: Archery
However they were already iconic. Ancient Egyptians domesticated them, Ancient Romans bred them. They were prized for their horns and meat.
Unfortunately the wild population of scimitar oryx dropped to less than 200 by the early 1980’s and within 10 years the last ever seen was in Chad. Declared extinct in the wild in 2000, they still existed in captivity.
Soon captive breeding programs looked for suitable locations in the Sahel for the antelope’s reintroduction and began breeding them in zoos and in herds to succeed in the wild. In the U.S., ranches in Texas breed them for reintroduction and for hunting.
To get an idea of what the animals look like, see this video from the Greater Vancouver Zoo.
Thanks to captive breeding, the first scimitar-horned oryx were released in Chad in 2016, as shown in this video.
Many endangered species go extinct before we know they exist. That didn’t happen to this iconic animal.
(photos from Wikimedia Commons, map from researchgate; click on the captions to see the originals)
If you’ve been watching white-tailed deer (Odocoileus virginianus) in the City of Pittsburgh you’ve noticed that they’ve changed their behavior since early September. Back then deer were easy find in groups during the day but now in October they seem to have gone missing. Soon — very soon — they’ll be running into traffic. All of this is part of their breeding season, called the rut, which is driven by photoperiod.
In late summer, white-tailed deer hang out in bachelor groups of adult males and matriarchal groups of does with fawns. As the rut goes through phases, described below, the dynamics change. In the city we live with so many deer that it’s good to know the phases.
Pre-Rut Phase: In late September and early October testosterone levels rise in the bucks, they rub on trees and shed velvet from their antlers. The bachelor groups break up as each male goes it alone and adjusts his home range. During this phase the bucks eat a lot, especially acorns. Once the rut begins they’ll be too busy to eat while chasing, breeding and tending does.
The buck rubs were fresh in Schenley Park on 9 October 2022. Right after this the bucks “disappeared” from the park.
Bucks also spar to settle their pecking order as shown in this photo from Tennessee. I have never seen sparring in the city parks.
Seeking and Chasing Phase: As the females begin coming into estrous the males search for and chase does in heat. The bucks move around lot, averaging 3-6 miles per day. Meanwhile doe+fawn groups break up as adult females become distracted. Watch out! They may run into traffic.
The late summer groups have already broken up in Schenley and Frick Parks. The only deer I’ve seen recently are lone females or almost grownup fawns.
At the peak of the rut bucks make long excursions out of their home range in search of females, sometimes 10-20 miles. The peak also includes a “tending” phase during which bucks and does pair up and hide in thick cover to breed repeatedly.
Post-Rut Phase: Activity drops off precipitously in early December after most of the does have bred. Adults stop wandering and settle into their home ranges. The males still have antlers and some will search for recently-matured fawns that come into estrous (red color in graph above), but the frantic edge is gone.
When will we see deer in lazy groups again in the city parks? Wait and see.
Dolphin skin constantly flakes and peels as new skin cells replace old cells. A bottlenose dolphin’s outermost skin layer may be replaced every 2 hours. This sloughing rate is 9 times faster than in humans. This turnover rate ensures a smooth body surface and probably helps increase swimming efficiency by reducing drag (resistance to movement).
We know these things about dolphins because some have a close association with humans. Veterinarians and trainers take an active interest in the welfare of animals in their care.
Dolphin veterinarians are especially concerned that as dolphins age, their heart health may suffer. This includes the dolphins in the U.S. Navy’s Marine Mammal Program in San Diego.
Last year the Navy asked for proposals to place heart monitors on their aging dolphins to unobtrusively monitor them as they move about in the ocean. There are many challenges to doing so including the dolphins’ skin. Because the skin turns over every two hours nothing can stick to it for long. I wouldn’t know about their skin if I hadn’t heard about the heart monitors.
The vast majority of us rarely if ever seen dolphins in the wild and know very little about their lives. We are mesmerized when we see them this close.
It’s hard not to love them.
(photos from Wikimedia Commons and from Royal Society Publishing; click on the captions to see the originals)
The season has changed and the woods in Schenley Park look different than they did a month ago. The trees are putting on fall color and deer are providing more evidence of their overpopulation in the park.
With the growing season over there is less greenery for deer to eat and there are fewer places to browse because they have already denuded many areas.
What is left has been eaten down to nubs, just visible above the unpalatable invasive plants. Below, goutweed nearly hides the tops of what used to be jewelweed while pokeweed was browsed to tiny leaves and bare stems.
As the greenery disappears deer eat tree saplings and small branches. In cases of deer overpopulation, such as Schenley Park, the young trees are foraged down to bonsai.