Why Evolution is True is a blog written by Jerry Coyne, centered on evolution and biology but also dealing with diverse topics like politics, culture, and cats.
A bullfrog (Rana catesbeiana) on the shore of Greenquist Pond, Somers, WI, 5 May 2021.
And speaking of late, it’s been a very late season for amphibians here in southeastern Wisconsin. The picture above is from May, 2021, because it’s been a very cold spring, and there’s been hardly any amphibian activity. Normally, chorus frogs (Pseudacris triseriata) begin calling in mid-March; this year I first heard them on April 7, and, since then, calling has been only sporadic. A year ago, American toads (Bufo americanus) began trilling the first week of May; I haven’t heard any yet. I have seen one adult bullfrog, in the last week of April. It was actually quite large– I spotted it with my naked eye across the Pond while scanning for turtles. (Turtles are out, but not in large numbers or consistently.)
Among the participating organizations is the Department of Defense PARC, which is charged with protecting and managing amphibians and reptiles on military lands, and they have been sending interesting items all week. One of the most fun ones for me was an amphibian identification quiz. It was done as a Powerpoint file, but I can’t figure how to set it up here in WordPress, so you’ll have to take my word for it đ . They sent a nice guide to modern amphibian origins:
And this set of links:
When folks think of migration, usually, people think of birds and whales carrying out this process. However, did you know that some of our amphibians migrate, too? When the night is right, thousands of spotted salamanders will make their way to temporary wetlands known as vernal pools to breed in the spring. Checkout this great video by the Tennessee Aquarium: https://youtu.be/8xGZ8SLqVa8
Looking for some educational inspiration to teach about salamander migration and vernal pools? If so, check out this resource list put together by Of Pools and People: https://www.vernalpools.me/ecology-2/
Check out how the Boreal Toad was brought back to Colorado by biologists working to reintroduce the species and how theyâve been affected by a decimating fungus: https://www.youtube.com/watch?v=x9RQVA_d1DU
Gifford Pinchot National Forest biologists created breeding habitat for the threatened Oregon Spotted Frog through an innovative interagency conservation project in this video: https://vimeo.com/278211745
As I’ve tweeted and also indicated in today’s Hili Dialogue, Bob Dylan turns 80 today. Reader Joe McClain called my attention to a letter that the President of Ireland wrote Dylan in honor of the occasion. It speaks for itself, though I didn’t know that the Irish President was a poet. Here it is (click to enlarge):
For the end of Amphibian Week, we have a photo gallery, starting with my late, lamented, Toady, who was collected by David Wingate, Bermuda’s foremost naturalist, in 1999, and who died in 2019, at the age of 20+ years. The Giant Toad, Bufo marinus, (also known as the Marine Toad or Cane Toad) is native to the continental American tropics and subtropics, and was introduced to Bermuda.
Giant Toad, Bufo marinus, Bermuda (collected in 1999; photo taken in 2012).
Note the enormous parotoid gland behind the eye, which secretes poisons that can protect the toad from predators.
Giant Toad, Bufo marinus, Bermuda (collected in 1999; photo taken in 2012).
My thanks to Chris, who has been distributing amphibian images, documents, and links throughout Amphibian Week. (If you’re wondering why the Department of Defense is involved in conservation, we’ve dealt with that before at WEIT. The short answer is that 1) the military must obey applicable environmental and conservation laws on military lands, and 2) certain animals pose practical issues for the military (e.g., venomous snakes). The Navy, which I know best, employs a number of professional herpetologists. Recall as well that the military has often enabled scientific exploration (the Beagle, for example, was a Royal Navy ship), and military reservations have sometimes had the best preserved habitats (e.g., much of the Patuxent National Wildlife Refuge was annexed from Fort Meade.)
Department of Defense Partners in Amphibian and Reptile Conservation. 2019. Department of Defense Herpetofauna Conservation Status Summary. Department of Defense Legacy Resource Management Program. pdf
The theme of today’s post is threats to amphibians.
In the above graphic, “41%” of amphibians are threatened”, may seem improbably precise, since threatened species are usually identified by the realization that some species is under threat, which then gets the species added to the IUCN’s Red List, an authoritative compilation. But the Zoological Society of London‘s Institute of Zoology has for a decade been implementing a “Sampled Red List Index“, which, instead of seeking out threatened species, assesses a large, random, sample of an entire higher taxon, thus giving a valid estimate of the proportion threatened. (I worked on the reptile SRLI, which assessed 1500 species).
One major threat to amphibians has been the global spread of the chytridfungus, Batrachochytrium dendrobatidis, which infects amphibians and can wipe out whole populations and species. Chris Petersen, of Department of Defense Partners in Amphibian and Reptile Conservation, sent me links to the following reports on surveys and assessments that have been conducted concerning the chytrid threat to amphibians inhabiting military lands.
I especially liked the first survey, a transcontinental transect study from California to Virginia; it found chytrid at all but one location.
Figure 1 from Petersen et al. (2011).
This and the second study were coauthored by, among others, my colleagues Rob Lovich and Mike Lannoo; Rob has previously treated WEIT readers to World Snake Day, and Mike has authored or coauthored several major works on amphibian conservation, including the monumental Amphibian Declines: The Conservation of United States Species. (The titles of these two reports also show the authors’ knowledge of song lyrics!)
We’ll finish off today’s installment with the non threatened Wood Frog (Rana sylvatica), which is widespread in North America. A northern species, a number of relict populations have survived in mountains south of the main range, left behind as the species followed the retreating glaciers north. This fellow’s from the main range in northern Minnesota, near Lake Superior.
Wood frog, Lutsen, near Lake Superior, Minnesota, 6 June 2014.
h/t C. Petersen, G. Wood
BĂśhm, M., B. Collen, … G.C. Mayer… et al. 2013. The conservation status of the world’s reptiles. Biological Conservation 157:372-385. pdf(MS)
Lannoo, M.J., ed. 2005. Amphibian Declines: The Conservation of United States Species. University of California Press, Berkeley. publisher
Petersen, C., R.E. Lovich, M.J. Lannoo, and P. Nanjappa. 2011. Do Frogs Still Get Their Kicks on Route 66? A Transcontinental Transect for Amphibian Chytrid Fungus (Batrachochytrium dendrobatidis) Infection on U.S. Department of Defense Installations. Proj. No. 09-246, Department of Defense Legacy Resource Management Program. pdf
Petersen, C., R.E. Lovich, C. Philips, M. Dreslik, P. Nanjappa, and M.J. Lannoo. 2013. From the Mountains to the PrairiesâSeasonal Bd Responses Differ by Latitude and Longitude at a Continental Scale. Proj. No. 10-426, Department of Defense Legacy Resource Management Program. pdf
Petersen, C., K.L.D. Richgels, G. Lockhart, and R.E. Lovich. 2019. Salamander Chytrid Fungus Risk Assessment on Department of Defense Installations. Department of Defense Legacy Resource Management Program. pdf
For the midpoint of Amphibian Week, Chris Petersen of Department of Defense Partners in Amphibian and Reptile Conservation sent me these amphibian facts.
Characteristics of Amphibians:
¡ Include frogs and toads, salamanders and caecilians (approximately 8,300 species worldwide)
¡ All are vertebrates (have a backbone)
¡ Are ectothermic (meaning they rely on external sources from the surrounding environment to maintain their body temperature)
¡ Most live part of their life in water and part on land (although there are many exceptions)
¡ Most have moist glandular skin through which they can respire (breathe) to various extents (some exclusively so, but most also through lungs or gills)
¡ Lay unshelled (jelly-like) eggs in moist to wet environments
¡ Most go through a process called metamorphosis to develop from a water-living life stage to a land-living stage
I then headed out to Greenquist Pond here at UW-Parkside to see what amphibians were about. You’ll recall that Chorus Frogs and American Toads have been calling on campus, but I hadn’t seen them at this pond. Here’s what I found.
Bullfrog, Rana catesbeiana, Greenquist Pond, Somers, Wisconsin, 5 May 2021.
I walked around three sides of the pond, and heard or briefly saw several Rana jump into the water, many emitting a little “yelp” as they dove in. I think both Green Frogs (Rana clamitans) and Bullfrogs (Rana catesbeiana) make that noise, so I wasn’t sure of the species. All were smallish, except for one that was bigger, but could have been either a large Green or a medium Bullfrog in size. I was heading back, reconciled to failure, when I spotted this medium-sized Bullfrog on the bank, which didn’t spook. I was able to get pretty close to get this shot, and even was using sticks to bend shadowing leaves out of the way, but it stayed put.
The Green Frogs and American Toads I showed in earlier Amphibian Week 2021 posts were also from this pond, but I’ve not seen them at the pond yet this year. (Some of the frogs today may have been Green Frogs.)
There were also turtles, so I’ll cheat a bit (they are reptiles, of course) and throw them in here. There were four five Painted Turtles (Chrysemys picta),
plus this Red-eared Slider (Trachemys scripta elegans), with another two Painted Turtles behind.
Red-eared Slider, Trachemys scripta elegans, and , in back, two Painted Turtles, Chrysemys picta, Greenquist Pond, Somers, WI, 5 May
There were a total of four five Painted Turtles, all with the slider in this corner of the pond. The slider is the most popular turtle in the pet trade, and is not native to Wisconsin. Although we find them not infrequently, they all seem to be released or escaped– they don’t seem to breed up here, even though they can survive the winters. (I had my own “Spot the …” moment– I didn’t see the further back Painted Turtle in the above photo until I’d posted it here!)
I’ve received another batch of amphibian goodies for Amphibian Week. Department of Defense Partners in Amphibian and Reptile Conservation suggests having a look at this video about the Hellbender (Cryptobranchus alleganiensis), a giant permanently aquatic salamander, and the largest (heaviest) amphibian in the Western Hemisphere. When I took herpetology as a summer course at Cornell University in upstate New York, there was a thrill when visiting a drainage in which hellbenders could occur; the mere possibility was enticing. Alas, we didn’t find any.
The Eastern Newt (Notopthalmus viridescens) and the Bullfrog (Rana catesbeiana) are common through much of the eastern US (the latter is also widely introduced in the west), and DoD PARC has produced fact sheets on both of them. This website explains, for kids, some of the differences between frogs and toads, but the problem with trying to distinguish frogs from toads is that there are many more kinds of members of the amphibian order Anura than just frogs and toads. “True toads” (Bufonidae) and “true frogs” (Ranidae) are only two of the dozens of families of anurans. We have two words in English, which correspond to the two genera (Bufo, toads, and Rana, frogs)Â which occur in England, but these aren’t enough; we tend to shoehorn that diversity them into either ‘frog’ or ‘toad’
We’ll finish off today with a species common in SE Wisconsin, the Green Frog (Rana clamitans). The relatively small eardrum would suggest this is a female, but it’s fairly small, and might just not have developed sexually dimorphic features yet.
Green Frog, Rana clamitans, UW-Parkside, Kenosha, WI, 20.ix.2015.
And here’s a bunch more. These were all rescued from a deep (ca. 20 foot) window well, and then released into nearby Greenquist Pond.
Green Frogs, Rana clamitans, UW-Parkside, Kenosha, WI, 20.ix.2015.
Sunday, May 2: What are Amphibians?
Monday, May 3: The Secret Lives of Amphibians
Tuesday, May 4: Amazing Amphibian Facts
Wednesday, May 5: Threats to Amphibians
Thursday, May 6: Amphibian Tweets from the Field
Friday, May 7: Partnering for Amphibian Conservation
Saturday, May 8: Actions for Amphibians
I began my Amphibian Week by hearing for the first time this year the trilling call of American Toads (Bufo americanus) yesterday afternoon, and I heard them again this morning. They were on my campus at the University of Wisconsin-Parkside, but not at the pond I was visiting, but I didn’t try to find out exactly where they were (I was tracking a family of Canada Geese both days). Here’s a calling toad from Pennsylvania, so you know what they sound like.
These were the first toads I’ve heard this season; Chorus Frogs (Pseudacris triseriata) have been calling since March 21 (a late start for them). I’ve featured our local American Toads a few times here at WEIT; here are a couple of featured WEIT toads from 2015.
American toads, Greenquist Woods, UW-Parkside, Kenosha, WI.
I missed this because I left out today’s anniversaries in the Hili dialogue. There are two big ones today, both pointed out by Fiona Fox, director of the Science Media Centre in Britain. Dr. Fox quotes remembrances from two of her experts (h/t Steve Jones):
FromProfessor Geoffrey L Smith FRS, Head, Department of Pathology, University of Cambridge
Today is VE-Day. [JAC: the 75th anniversary.] It is also the 40th anniversary of the WHO declaration of the eradication of smallpox, which in the 20th century alone killed an estimated 400 million people, many more people than in both world wars. Whilst in the midst of another viral pandemic, we should remember the magnificent role that WHO played in ridding the world of smallpox and the power of vaccination. WHO should be encouraged, supported and funded in its efforts to control and eliminate COVID-19.
Quoting Macaulay, History of England 5, 2468-70, (1914)
âSmallpox, the most terrible of all the ministers of death: The smallpox was always present, filling the churchyard with corpses, tormenting with constant fears all whom it had not yet stricken, leaving on those whose lives it spared the hideous traces of its power, turning the babe into a changeling at which the mother shuddered, and making the eyes and cheeks of the betrothed maidens objects of horror to the loverâ
Edward Jenner predicted the global eradication of smallpox in 1801 when he said
âit now becomes too manifest to admit of controversy that the annihilation of the smallpox, the most dreadful scourge of the human species, must be the final result of this practiceâ
Now let us do this to COVID-19.
JAC: Here’s what smallpox does even when it spares a life. This child will be irreparably scarred:
From Wikipedia: A child with smallpox in Bangladesh in 1973. The bumps filled with thick fluid and a depression or dimple in the center are characteristic.
And here’s the resolution: short, sweet, and succinct:
From Michael A. Skinner, PhD FRSB, Reader in Virology, Imperial College London
With attention focused on the 75th anniversary of VE Day, and distracted by the COVID-19 pandemic, an important anniversary may pass us by, with some relevance to our present situation.
On 8 May 1980, the 33rd  Assembly of the World Health Organisation officially endorsed the successful eradication of smallpox in October 1979.
Several points are noteworthy:
Smallpox (with a mortality rate of about 30%) killed 300 million people in the 20th century alone (three times the death toll of both World Wars), and 500 million in its final hundred years).
– Smallpox is believed (informed by virus genome sequence data) Â to have âjumpedâ from an animal source millennia ago (there is good evidence it was present in ancient Egypt)
– No one can therefore seriously suggest that the variola virus that causes it arose from anything other than a natural source.
– Infections were controlled and reduced by vaccination; the disease was finally eradicated by a massive global campaign spearheaded by WHO.
– That campaign relied on rigorous and extensive field epidemiology, using a âtrack, trace and [ring] vaccinateâ approach (with no rapid molecular diagnostics available at the time, diagnosis relied on recognition of the distinctive lesions and other symptoms)
– The final battlegrounds for the eradication were Bangladesh, Ethiopia, Kenya and Somalia, where the last natural case was identified.
And here’s a quiz for you. Another deadly viral disease, but in animals, has also been completely eliminated by a combination of monitoring and vaccination. This one was declared eliminated in 2011. Do you know the disease? Look here for the answer.
Today is the 60th birthday of reader Hugh Dominic Stiles, who posts under “Dominic” and is known to his friends as “Dom.” (See the birthday section of today’s HIli Dialogue.) Dom’s contributed a lot to this site over the years, both through commenting and sending me tons of interesting items, and I thought I’d give him a shout-out. He works for the medical library at University College London, but, like all UCL employees, can’t go back to work for a while. Dom’s friend Jeremy sent me the notice of his birthday and a photo of Dom, as well as a short narrative of his life (indented below).
I first met Dom when he was a stonemason at Chichester Cathedral in the early 1980s. He subsequently moved to St Paul’s Cathedral in London, where he concealed his underwear, together with runic curses that he had etched into lead, in places where they might not be discovered for several centuries to come. While at St Paul’s, Dom was able to give those of us lucky enough to be his friends tours in which he had access to areas the general public could never dream of visiting.
Dom loves cold, wet, and generally disagreeable weather. This was possibly a factor in his choice to study in Norway, where he obtained his bachelors degree. He is extremely modest, despite being the cleverest person I know. Whether the subject is history, geography, biology, or something else, Dom always has a knowledgeable and interesting perspective.
I’m including a photo of Dom taken by one of my kids about five years ago. It’s a perfect example both of his silliness and the fact that he always has his head in a book!
Happy 60th, Dom!
On another note, I’d like to revive the “photos of reader” feature during quarantine, so if you’d like to be featured, send me a photo of yourself doing whatever you do while locked down (2 photos max) and a very short explanation or narrative. Thanks!
