Category Archives: Mammals

Dolphins Just Wanna Have Fun

Northern right whale dolphin, Monterey Bay, Calif. 30 Nov 2022 (photo by Robin Agarwal via Flickr Creative Commons license)

4 December 2022

Dolphins are very intelligent and engage in many kinds of play. Robin Agarwal photographed their antics while on a pelagic tour in Monterey Bay on 30 November 2022. For instance …

The northern right whale dolphin (Lissodelphis borealis) in mid-leap, above, looks super sleek because he has no dorsal fin.

A Pacific white-sided dolphin, below, went way beyond mere jumping. He leapt, turned, and sometimes entered the water tail first. Somersaults!

Dolphin somersaulting! Pacific white-sided dolphin

Here’s a calmer view of this species (Lagenorhynchus obliquidens) with a cape of bubbles from his spout.

Pacific white-sided dolphin surfaces with a cap of bubbles on its back, Monterey Bay, Calif, 30 Nov 2022 (photo by Robin Agarwal via Flickr Creative Commons license)

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.”

Dolphins stampede toward the whale watch boat in order to bow ride, Monterey Bay, Calif. 30 Nov 2022 (photo by Robin Agarwal via Flickr Creative Commons license)

Here they are bow riding with an “unusual swirl color morph” among them.

Unusual ‘swirl’ color morph Northern Right Whale Dolphin joins the other NWRDs and Pacific White-sided Dolphins at the bow

Dolphins just wanna have fun!

Check out the great photos by Robin Gwen Agarwal on Flickr.

(photos by Robin Gwen Agarwal on Flickr Creative Commons license.)

The Largest Living Organism is Dying of Deer

Pando in October snow, 2021 (photo by Beth Moon via Flickr Creative Commons license)

29 November 2022

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.”

Quaking aspen, Pando, in fall (photo from Wikimedia Commons)

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.

Aerial image of the location of the single aspen tree, Pando (highlighted in green) at Fishlake National Forest, Utah (photo from Wikimedia Commons)

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).

Mule deer in Colorado (photo from Wikimedia Commons)

So they fenced it — twice — one fence in 2013, another in 2014.

Map of 2018 Pando study partially funded by U.S. Bureau of Land Management, Grant/Award Number: L21AC10369 (map downloaded from Wiley Online Library)

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.”

Sci.News, October 2018: Pando, World’s Largest Single Organism, is Shrinking

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.

Aldo Leopold: Sand County Almanac, “Thinking Like a Mountain”

Pando’s days are numbered because new trees are not growing up to replace the old ones. This is how a forest dies.

(photos from Wikimedia Commons, map from Wiley Online; click on the captions to see the originals)

Did You Sleep Enough?

The Nap (painting by Jan Verhas, 1879)

20 November 2022

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!

Goats and guard donkey at Frick Park in Aug 2020 (photo by Kate St. John)

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.

Cat sleeping on man (photo from Wikimedia Commons)

Adopted greyhounds are champions at sleeping 18 hours a day.

Greyhound sleeping (photo from Wikimedia Commons)

Brown bats have one of the longest sleep cycles at almost 20 hours (19.9 hours per day according to this table).

Little brown bat sleeping (photo from Wikimedia Commons)

Birds are in the middle, sleeping 10-12 hours a day, but their sleep is highly variable by species, place and season, especially in the Arctic where a summer “day” can be 24 hours long.

Sleeping duck (photo from Wikimedia Commons)

Guppies sleep slightly less than humans at 7 hours a day.

Trinidadian guppies (photo from Wikimedia Commons)

And giraffes win the prize for the least sleep at only 1.9 hours a day!

Giraffe (photo from Wikimedia Commons)

Did you get enough sleep last night? No? Then it’s time for a nap!

For more information see:

(photos from Wikimedia Commons except where indicated; click on the captions to see the originals)

November Deer in Pittsburgh

Doe on the trail in Frick Park, 10 Nov 2022 (photo by Charity Kheshgi)

13 November 2022

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.

4-point buck on the trail looks down at the 8-point and two does, 10 Nov 2022 (photo by Charity Khseshgi)

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.

10-point buck in Frick Park, 5 Nov 2022 (photo by Mike Fialkovich)

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.

Map of Pennsylvania WMUs from PA Game Commission

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
  • Nov. 26 – Dec. 10 including Sunday Nov. 27: Statewide Rifle (“Regular firearms”)
  • Dec. 26 – Jan. 28, 2023, WMU 2B:
    • Archery
    • Flintlock
    • Extended Rifle season (Antlerless only).
Wear Orange and be alert for hunters! Note hunting on three Sundays in November.

p.s. When you’re on the road, watch for deer running into traffic, especially at dusk.

(photos by Charity Kheshgi and Mike Fialkovich, WMU map from PA Game Commission, calendar marked up from

Come Closer. Listen.

Spanish red deer stag, Cervus elaphus hispanicus (photo from Wikimedia Commons)

11 November 2022

Spanish cellist Diana Gomez plays music outdoors in many venues. Here’s what happened when she took her cello into a forest and played Bach’s Suite No.1.

Come closer. Listen.

The stags that approached her are red deer (Cervus elaphus), native to Europe and one of the largest deer species. Spanish red deer (Cervus elaphus hispanicus) are not as red as other members of the species.

To hear more from Diana Gomez check out her YouTube channel at Chelodiana or follow her on Instagram at Chelodiana. Her video Ocean includes cameo appearances of egrets and flamingo.

p.s. Two years ago Roger Day played Bach on his tuba in Frick Park and, in his words, “got only cicadas” to respond. Check out his video here.

(photo from Wikimedia Commons; click on the caption to see the original. video from Chelodiana)

Preserving an Iconic Animal

Scimitar-Horned Oryx, (Oryx dammah) in Marwell Zoo, Hampshire, UK (photo from Wikimedia Commons)

7 November 2022

The scimitar-horned oryx or scimitar oryx (Oryx dammah) is extinct in the wild but not extinct on Earth. These iconic animals still exist because their beauty prompted us to preserve them.

Scimitar-horned oryx are desert antelopes that can survive without water for months or years by absorbing water from the plants they eat. Native to the Sahel (pink on map below), there may have been 1 million of them at the height of their population in the early Holocene (9500–4500 BPE) but they declined over the centuries due to climate change and hunting.

Map of the Sahel from

However they were already iconic. Ancient Egyptians domesticated them, Ancient Romans bred them. They were prized for their horns and meat.

Scimitar oryx at Chester Zoo (photo from Wikimedia Commons)

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)

City Deer in the Rut

Doe drinks from a pond in Homewood Cemetery, Pittsburgh, 10 October 2022 (photo by John English)

25 October 2022

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.

Buck on a tree, Fall 2008 (photo by USFWS Mountain-Prairie via Flickr Creative Commons license)

The buck rubs were fresh in Schenley Park on 9 October 2022. Right after this the bucks “disappeared” from the park.

Buck rubs in Schenley Park, 9 October 2022 (photos by Kate St. John)

Bucks also spar to settle their pecking order as shown in this photo from Tennessee. I have never seen sparring in the city parks.

Two bucks locking antlers, Great Smoky Mountains, Tennessee (photo from Wikimedia Commons)

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.

Peak of the Rut: According to The Whitetail Rut in Pennsylvania, the peak in Pennsylvania lasts about five weeks, 29 October to 3 December. Their graph, embedded below, is tiny on purpose so that you will look at the original graph, including date ranges, on the Boone & Crockett Club website.

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.

11+ deer in Schenley Park, Cathedral of Learning in distance, March 2019 (photo by Kate St John)

Resources for this article:

(photos by John English, Kate St. John and Creative Commons licenses from USFW Flickr and Wikimedia Commons. Embedded graph from Boone & Crockett Club website)

Busy as a Beaver

Beaver gnawing a tree, Wilhelma Zoo (photo from Wikimedia Commons)

21 October 2022

No matter where they live beavers (Castor canadensis) must gnaw wood every day to wear down their constantly growing front teeth. In captivity they are given wood to keep their teeth healthy.

A beaver in rehab doesn’t have to make a dam but it’s obviously an instinct that’s hard to deny. He builds a dam at the doorway.

Busy as a beaver!

(photo from Wikimedia Commons, embedded video from YouTube)

Dolphins Shed Their Skin Every 2 Hours

Dolphin playing in the wake, Everglades (photo from Wikimedia Commons)

16 October 2022

Dolphins have specialized skin for their underwater lives. The outer layer (epidermis) feels rubbery and is 15 to 20 times thicker than our own. It stays smooth because:

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). Bottlenose dolphin characteristics

Dolphins will even take turns to rub their bodies on corals and sponges, an activity that probably feels good. (video: Why Taking Turns Is Good for Dolphin Skin)

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 looking above the water, Kyoto Aquarium (photo from Wikimedia Commons)

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.

Photo from 2003: Dolphin wearing geolocator during mineclearance operations, US Navy Marine Mammal Program (photo from Wikimedia Commons)

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.

Fascinated by dolphins, Dolphin Bay (photo from Wikimedia Commons)

It’s hard not to love them.

(photos from Wikimedia Commons and from Royal Society Publishing; click on the captions to see the originals)

October With Too Many Deer

Colorful leaves, Schenley Park, 9 Oct 2022 (photo by Kate St. John)

10 October 2022

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.

Doe browsing in Schenley Park, 21 Aug 2022. NOTE: A buck-rubbed sapling is in the foreground (photo by Kate St. John)

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.

Nothing growing on the ground in the presence of too many deer, Schenley Park, 9 October 2022 (photo by Kate St. John)

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.

Favored plants are browsed to the tops of unappetizing plants (goutweed), Schenley Park 9 Oct 2022 (photo by Kate St. John)
Pokeweed overbrowsed by deer, Schenley Park, 9 October 2022 (photo by Kate St. John)

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.

Ash tree sapling overbrowsed by deer, like bonsai, Schenley Park, 9 Oct 2022 (photo by Kate St. John)

Schenley no longer has enough food for deer so at night they walk into neighborhoods and browse in backyards. This is happening across the city and has prompted some residents to consider a Deer Management Plan for Pittsburgh. KDKA’s Andy Sheen reports: Some Pittsburgh residents say it’s time to get deer population under control. Click on the link or the screenshot below.

Some Pittsburgh residents say it’s time to get the deer problem under control, KDKA Andy Sheehan

(photos by Kate St. John + screenshot from KDKA)