The sad natural history of Mauritius

It's weird to find out about it by reading Salman Rushdie's memoirs book Joseph Anton, but I only found out today that the now-extinct dodo was endemic only to the island of Mauritius. Furthermore, the island used to boast a whole slew of other, much less known, flightless or near-flightless birds, all now extinct also.

Mauritius is a speck in the Indian Ocean, about two thousand kilometres off the coast of Africa. The only other places even vaguely close are another speck called Réunion, and a the much larger island of Madagascar. It's the original island paradise - white sand beaches, turquoise lagoons, lush volcanic peaks - but man, is it isolated. 

The seafaring Dutch found it, though, at the end of the 16th century, at which time it was entirely uninhabited but chock-full of endemic birds and animals. By the time the Dutch left, just over a hundred years later, they (and their dogs and imported rats) had managed to kill off almost all of the native species, including the dodo. The French then moved in and established a sugar industry based on slave labour. A century after that, the British moved in to Mauritius and abolished slavery, but brought in hundreds of thousands of indentured workers from India (slavery lite), the descendents of whom still live there today.

So, a sorry history, to be sure. But it was all the extinct flightless birds that intrigued me. The dodo we know about, but Wikipedia has a whole page of links on the extinct animals of Mauritius, many of them flightless or at least flight-challenged birds, like the red rail, the Mauritius sheldgoose, the Mauritius ground thrush, the broad-billed parrot, the Mauritius blue pigeon, the Mauritius scops owl, the Mauritian turtle dove, the Mascarene coot, the Mascarene grey parakeet, etc. 

In addition to flightlessness, or at least poor flight ability, these birds, and many of the other Mauritian animals now extinct, these birds were terminally naive and trusting, having developed with no real predators, and certainly nothing like the rapacious humans now moving into the area.

Imagine being a Dutch explorer back in 1598, arriving on the pristine shores of Mauritius, full of curious ground-based animals and birds. What would you have done? Probably killed as many as possible. We were a pretty savage bunch back then.

A plague of frogs?

I obviously missed it at the time, but back in the innocent days of June 2005, a rather bizarre event occurred in the small town of Odžaci in northern Serbia, when storm clouds gathered and thousands of frogs rained down total the ground.

Traffic ground to a standstill and the locals ran for cover as "countless" frogs fell from the air with the rain. The frogs, described as different from the frogs usually seen in the area, seemed to survive the fall, and just hopped away, to everyone's surprise.

This is an unusual, but not unique, occurrence. A downpour of frogs has been reported in Tournai, Belgium in 1625, in Lille, France in 1794, in Kansas City, USA in 1873. Pink frogs were reported to have rained on two towns in Gloucestershire, UK as recently as 1987. 

And frogs are not the only animals to fall from the sky: the small town of Yoro, Honduras celebrates an annual Festival de la Lluvia de Peces (Festival of the Fish Rain), when a rain of small silvery fish falls once or twice a year. If it's happening, I guess you may as well celebrate it!

This is not quite the Biblical plague of frogs described in Exodus 8 verses 1-15. That was actually a much less impressive event, where an unspecified number of frogs ("abundant", millions?) came out of the river (the Nile?) and "covered the land of Egypt", getting "into the houses of your servants, onto your people, into your ovens, and into your kneading bowls". No, not the kneading bowls! Deprived of water, the frogs eventually began to die off, causing a "great stench".

This must have been concerning, but the divine threat "I will smite all your territory with frogs" was perhaps not one of the Lord's most chilling. Certainly, it didn't change Pharaoh's mind on the captivity of the Israelites, because God tried eight other plagues after the frogs.

There is of course a perfectly good explanation for all these miracles, and it doesn't involve God or smiting. Regarding the rain of frogs, there is a freak meteorological event called a waterspout, where a small tornado forms over water, sucking up any lightweight objects into its extremely low-pressure centre. When the tornado loses energy and dissipates, it rains its contents to the ground wherever it happens to be. Some waterspouts can travel hundreds of kilometers, but usually they only travel a few kilometers from their source. 

The Biblical plague of frogs can have many natural explanations (as do the other plagues and miraculous events mentioned in the Bible), from a regular migration to a one-off stress reaction caused by water pollution or algae blooms or bacterial or viral agents or increased water temperatures or drying up of parts of the river due to short-term climate events or Super El Niño years.

Weird things happen in nature. You can understand that ancient religious leaders (the politicians of their day) might have been tempted to use them for their own advantage, much like even more ancient leaders used knowledge of astronomical events, extreme weather, etc, to bamboozle and control their naïve citizens.

Offshore wind farms may actually help wildlife

Detractors of wind power - the Donald Trumps of this world - and even environmentalists who would otherwise have been in favour, often claim that wind turbines, and especially offshore wind turbines, are deleterious, even downright dangerous, for wildlife and biodiversity. Opponents point to the disruption of the marine environment during construction (and decommissioning) of offshore wind turbines, the distraction of larger fish and whales due to the noise and vibration of the turbines, and the effects of electromagnetic fields around them, although the ramifications of many of these issues are still not well understood or proven.

But data from Europe over the last few years is starting to tell a different story. It turns out that European windfarms in the North Sea may actually be offering new areas of protection for marine wildlife, including for some threatened species like great seals and North Sea cod. The huge underwater turbine towers can provide a home for some species, and reefs of marine life have begun to form on them (the construction of artificial reefs is also a possibility). They also provide protected areas where fishing vessels cannot access, thus reducing the risks of overfishing.

Other research shows that, while the construction phase of offshore wind turbines does disrupt fish and predator numbers, they very quickly come back after construction is completed, often in even larger numbers, as stationary and mobile species use the constructions as a kind of ready-made reef. Predators like seals also come back in turn. They may change their methods of hunting a bit but they too seem very happy with the new additions to the seascape.

The jury is still out and more research and data is needed, but it is possible that the positive side effects of wind farms may outweigh any unfortunate negative ones.

Maybe cows are not all stupid

If you thought that cows were pretty stupid, well, you're probably right. But maybe not AS stupid as you thought.

It turns out that cows have joined the relatively exclusive club of tool-wielding animals, in the company of humans, chimpanzees, crows, and maybe humpback whales.

And before we get too excited, it's really only Veronika, a 13-year old Swiss Brown cow that lives on a farm in Austria, essentially as a pet. Veronika, over the years, has perfected her technique of using sticks or brushes to scratch herself in various places. It's not much maybe, but it's enough to get some animal behaviourists quite excited.

All those other cows? Yeah, pretty stupid.I 

One of the world's weirdest plants

It looks like a kid's plasticine model of a fungus, or possibly some kind of sex toy, but it's actually one of the world's weirdest plants. This is balanophora fungosa. It doesn't really have a common name, although it's sometimes called fungus root. It's said to smell like mice!

It's pretty rare, growing only in the steamy subtropical mountains of Taiwan and parts of Japan. It has some close relatives in South Asia, South-East Asia, Australia and some Pacific Islands. It's actually an angiosperm, or flowering plant, related to, you know, daisies, roses and such like, but it's very different from daisies and roses in several respects.

For one thing, it contains no chlorophyll and so does not grow by photosynthesis like most plants. It also lacks a conventional root system, instead attaching itself to the roots of nearby trees and stealing its nutrients parasitically (although it does still retain some plastids, the organelles that normal plants use to enable photosynthesis).

The plant can also reproduce without fertilization, which is very rare in the plant world, using a process known as "facultative aganospermy" - essentially, it clones itself. This can be useful, but it also leaves it highly vulnerable to habitat loss, as it is very dependent on specific conditions and tree hosts.

It does technically have flowers and seeds, some of the smallest flowers and seeds in the plant world. Thousands of tiny female flowers are contained the bulbous structure at the top, with a much smaller number of male flowers are at its base.

So, yes, pretty weird. And, of course, given its very specific habitat and the encroachment of humans, it's endangered.

Marineland should be paying to relocate beleaguered belugas

The saga of the Marineland beluga whales continues, as the financially-troubled Niagara amusement park says it can no longer afford to feed the whales, and is calling on the federal government to bail it out, after years of exploiting the whales for its own profit. In fact, it says it will start to euthanize the belugas if some level of government doesn't come through with funding. Not only is this an attempt at blackmail, it is a complete abdication of responsibility.

The park, which uses whales for entertainment and has already managed to kill 19 belugas and an orca since 2019, is effectively holding the beluga as hostages. It says it had arranged for the whales to be sold to a Chinese amusement park where they would probably be kept in even worse conditions. But the government has (quite rightly) nixed such a move and refused to grant export permits, on the grounds that it would be against the Fisheries Act and Criminal Code to allow the whales to face a future of exploitation, performing tricks in captivity.

The chutzpah of Marineland beggars belief. They should sell every last asset they possess in order to relocate the belugas to somewhere they can live out what remains of their lives in some level of comfort and freedom. Various non-profits and municipalities in Nova Scotia, Newfoundland and Northern Quebec have made overtures towards taking the whales, but it is Marineland that should be paying for this.

Orchid mantis - disguise not camouflage

Here's a video, apropos of nothing at all, of an orchid mantis, one of the world's most beautiful insects.

Looking for all the would like a beautiful pink orchid, the mantis actually attracts more pollen-seeking insects than even a regular orchid. The difference is that visiting insects never leave, gobbled up by the voracious mantis.

The Southeast Asian insect is not exactly camouflaged - it WANTS to be seen - but it's certainly in disguise.

Is milkweed really poisonous?

You probably know (if you're North American at least) that monarch butterflies lay their eggs on milkweed plants, the idea being that when the caterpillars hatch, they feed on the milkweed, which is poisonous for most animals. Monarchs, though, are resistent to the milkweed's toxins, and so can safely ingest it, and in the process become poisonous and bad-tasting themselves. Birds and other predators know this, so the story goes, and so avoid attacking and eating them.

This is well known, as is the ancillary story that viceroy butterflies developed the evolutionary trick of mimicking the monarch, even though their caterpillars do not feed on milkweed (although it turns out, this story is actually not quite as simple as most people think).

But, from my own anecdotal observations, it seems that a whole host of other insects also feed on milkweed - beetles, ants, bees, wasps, you name it. The most common one I see is the milkweed beetle, which is also red to warn off predators. (In fact, I rarely actually see monarchs on them!) But many other insects, moths and birds like hummingbirds do eat milkweed, although perhaps not as exclusively as monarchs.

Red milkweed beetle

So, how poisonous can milkweed really be? Have all these other insect also developed a resistance to milkweed's toxins? Have we been mislead all these years?

Well, yes, milkweed is indeed poisonous. It contains a toxic substance called cardenolide which, if ingested in large enough quantities - and there's the key - can cause cardiac arrest in humans, livestock and other animals. But is also tastes really bad, so instances of cattle poisoning, etc, are very very rare. Livestock will not eat milkweed unless they are very desperate. Similarly, pets will find your garden milkweed very disagreeable to eat, and so will typically stop before any harn can occur.

Several different species of insects are commonly found on milkweed plants, including: large and small milkweed bugs; swamp, red and blue milkweed beetles; milkweed aphids; and the showy milkweed tussick moth caterpillar. Like the monarch, these insects have developed a resistance to milkweed toxins, and some can even sequester the toxins in certain special glands.

So, poisonous? Yes, to an extent. Exclusive to monarch butterflies? Nope.

A highly symbolic encounter between a Canada goose and a bald eagle

Seems appropriate to share this. 

An Ontario photographer captured this stand-off between a Canada Goose and a Bald Eagle on a frozen lake near Burlington, ON, recently.

While you might think the conclusion was foregone, it turns out that the plucky goose fought back bravely against the eagle's attacks, and eventually the eagle gave up and flew away.

Rife with Canadian and American symbolism, this encounter might give hope to the underdog Canadians, as the US goes all out to dominate Canada through tariffs and other means, and Canada does what it can to fight back.

What's the truth behind the fabled "seventh wave"?

As I sit watching the waves on a beach at the less trendy end of Grand Cayman, I got to wondering about the truth about the mythical (pr perhaps not) "seventh wave".

The truth, as these things usually turn out, is complicated.

The short answer is that the old saw is nonsense: ocean waves are generated by the wind way out to sea before they crash onto the beach, and the wind is capricious and unpredictable. Why then, should we expect waves to be regular?

However, once a few waves get going and begin to feed off and amplify each other, they do become a bit more coherent and regular, and in practice they do tend to form packs or groups of between 12 and 16 waves, with the biggest waves in the centre of the pack. So, the group of waves typically goes from small to big and back to small again, with the largest wave of the group right around number seven or eight.

However, that does still mean that the largest waves only occur every 12, 14 or 16 waves, not the 7 of folklore. Sorry.

And just while we are about it, why do waves break anyway? Waves out at sea are caused by the wind imparting its energy and friction to the waves it comes into contact with. But waves out at sea usually don't break - they just cause bigger and bigger swells.

When the waves approach a coastline, though, the water is shallower and there is less water to draw up into the wave. At the same time, there is more friction acting on the bottom of the wave (where it meets the seabed) than there is at the top. So, the bottom is slowed down more than the top until eventually the top of the wave kind of overbalances and topples over itself due to the force of gravity. This is what we see as the wave breaking. So, there you go.

A moth that build a log cabin

There are some pretty strange critters out there with some pretty bizarre habits. But a new one to me is the Bagworm Moth (Psychidae), whose caterpillar saws little twigs and sticks and builds them into miniature log cabins for themselves.

Neat, huh? The log cabins are even mobile and move around with the caterpillars. The logs are held together with silk that the caterpillars produce, and they actually build the edifice on their own backs.

Interestingly, only the males of the species transform into adult moths. The females stay in a mature larval state, and never grow wings and legs like the males. The males only live for a few days after mating, although the females live longer while her duties call. The eggs stay safe and warn in the log cabin, while the females tend them. 

Cool.

The world's loudest bird

You might get annoyed by noisy crows of seagulls at times, but think yourself lucky you don't live in the Amazon rainforest where you might wake to the dulcet tones of the white bellbird.

This bird has been recorded at 125 dB - about the equivalent of a pneumatic drill - and not much more euphonious either!

A little fish with a whopping genome

Lungfish are strange animals. Air-breathing fish that can hop onto land using weird limb-like fins, they are ancient animals, largely unchanged in 300-400 million years, earning them the label "living fossils". They may also be the closest living relative to the original tetrapods, the ancestors of all vertebrates, including us.

But it turns out they are stranger than we ever thought. Scientists have been sequencing the genomes these strange beasts, and this has yielded some unexpected results. Starting with the Australian lungfish and then the African lungfish, researchers have been surprised at the size of the genomes. But the recently sequenced South American lungfish (Lepidosirem paradoxa) has blown them all away.

This ancient fish has a genome with about 91 billion base-pairs in its DNA, about 30 times the size of the human gemome. However, only about 20,000 of these genes actually code for proteins. About 90% of them are "transposable elements" (TEs), highly repetitive "jumping genes" copied from elsewhere in the genome, possibly as a result of interaction with so many viruses over the eons.

Carrying around so much genetic material has its drawbacks. For one thing, it takes a lot of energy to repeatedly copy all that DNA into new cells, and the cell nuclei and the cells themselves have to be physically bigger. That said, the extra DNA may come in handy if the fish needs to adapt to changing environments, because the TEs can ramp up or down expressions of certain genes, allowing for more rapid adaptation, which maybe why lungfsh have survived quite so successfully thus far.

And it may not end here. The marbled lungfish is thought to have a genome 50% bigger still, which would make it far and away the largest genome of any animal, although the full sequencing remains to be done. 

And even that pales at the side of Tmesipteris oblanceolata, a tiny fern from Eastern Australia, commonly called a fork fern. This simple little plant has a humungous 160 billion base-pairs in its DNA, more than 50 times more than human beings, thus proving definitively that an organism's complexity is completely unrelated to the size of its genome.

Eagles stop cormorant removal work

Urban wildlife management is hard. This is known. 

The double-crested cormorant (the official name of the regular everyday cormorants we see around the Great Lakes) was in terminal decline a few decades ago, mainly due to toxic pesticides like DDT. Due to conservation efforts, it made a miraculous recovery, and now has a very healthy summer population in the area - perhaps too healthy.

Thing is, they are pretty unpleasant birds. Perhaps their worst habit is killing off the very trees they nest in - their guano or droppings is very acidic, as well as pungently, putridly smelly, and kills their nesting trees over time. You might have seen (and smelled!) the blighted area of trees towards the tip of Tommy Thompson Park (better known locally as the Leslie Street Spit), just offshore from downtown Toronto, where they have nested for some years now.

Having killed off that area of trees, the cormorants thought it a good idea to move just across the bay to Centre Island and infest a grove of trees there. But Centre Island is a tourist area and adjacent to the small community of people who live on the islands. Toronto naturalists and park managers tracked the move and have been trying to deter the cormorants from settling on Centre Island

However, that work is now on hold. The reason? Two bald eagles moved in to a cormorant nest on Centre Island this spring, spruced it up, tripled its size, and this has those same naturalists very excited. Because, other than another nesting pair that made an undisclosed Toronto ravine home earlier this year, these are the first bald eagles ever to settle in Canada's most populous city.

So, the cormorant removal work promptly stopped in order to give the eagles some space, and now the cormorant population on Centre Island has mushroomed from about a thousand to at least two thousand. The eagles have been seen snacking on cormorants, but that's not going to be enough to discourage them from wrecking the trees of Centre Island. 

*Sigh* What to do? Well, now that two healthy eaglets  have fully fledged from the nest, Toronto Region Conservation Area personnel believe they can now continue their work of aggressively relocating the cormorants back to Tommy Thompson Park. And I guess they will do the same thing all over again next year if the eagles return.

Where are those monarchs?

I saw my first monarch butterfly of the year just yesterday, 4th July, here in Toronto. I swear it gets later every year.

It's hard to find hard information on monarch numbers on a timely basis, despite them being probably the most researched butterflies in the world. The best I can find is a late June report by Monarch Watch, which seems to suggest that there is nothing to worry about.

Despite the winter monarch count in Mexico being the second-lowest ever recorded and some low early numbers of migratory returnees, Monarch Watch says that they take comfort in the fact that the early arrival were just that, early. 

"It seems safe to say that the numbers indicate that the growth of the population this year is comparable to that of most populations since 2015. The recovery to this point is nothing short of extraordinary and is a testament to the monarch's resilience."

Hmm, OK. That doesn't gel with my own observations of increasingly late arrivals and low numbers here in Toronto. So, what to think? Wait and see, I guess.

The raccoons are taking over

I hadn't realized it, but apparently raccoons are on the move. Indigenous to the USA and southern Canada, they are increasingly being found in places like Western Europe, Central Asia and Japan. And, with climate change, they are moving into areas where they used not to be found. One study suggests that over 60% of the world is currently suitable for the "raccoon invasion". And wherever they go, they establish a love-hate relationship with the local humans.

We are used to raccoons (affectionately known as "trash pandas") here; they are just part of the environment we live in. Toronto, in particular, is Raccoon Central. We can admit that they are cute, smart, dextrous, curious and interesting animals, but at some point this always tips over into annoying, troublesome, destructive, even detested. The residents of some of the newer raccoon habitats are just starting to realize that.

Raccoons were imported into places like Germany in the 1930s and 40s to farm for their pelts, and of course some of them eventually escaped (or in some cases were deliberately released, just for the hell of it). Japan had something of a love affair with raccoons after a popular children's book was televised in the 1970s, and thousands of Japanese children wanted pet raccoons of their own. Of course, that didn't go well, and many escaped or were quietly released when it was realized that they don't make good pets. In other places, they were used for medical experiments, alongside mice and rats. But, unlike the mice and rats, they managed to escape from there too.

Raccoons as an invasive species have proved difficult to eradicate. They are consummate survivors. Their birth rate is prodigious, and a surprising proportion of babies survive into adulthood, even in a hostile city environment. They can eat almost anything, and can find their way into the most unlikely of hiding places. 

Several years ago, the city of Toronto spent millions of dollars on raccoon-proof compost bins, only to find that their strong, clever little paws found a way into them anyway. (The most recent version of a city compost bin seems to be keeping them at bay ... for now!) Bungee cords just don't cut it. You can now buy t-shirts with "Raccoons vs. Toronto" logos here, or "Home is Toronto" with a raccoon poking out of a trash can, or "Raccoon City". For the most part, we have come terms with living in their city.

So, good luck Germany. Good luck Japan. From our experience, the best you can hope for is a grudging coalition; at worst, expect them to take over. In the meantime, maybe invest in some raccoon-proof bins. And maybe a t-shirt.

Meet the hammer-headed bat

Couldn't help but share a picture of a hammer-headed bat, the largest of all African bats.

These so-ugly-they're cute animals glory in the Latin name Hipsignathus monstrosus, and their similarity to medieval gargoyles has not been lost on researchers. 

They live in the lowland forests of west and central Africa, and eat fruit like figs, guavas, bananas and mangoes, as well as flies and other insects, and even scraps of bird meat and chicken blood. Their wingspan is an impressive one metre, and they wrap their wings around their huge noses to sleep. The boxy elongated heads of the male bats contain a large resonating chamber that amplifies their calls and honks. In fact, their voice box or larynx takes up fully half or hie body cavity, and other major organs are pushed way back by it.

They make particular use of this prodigious voice box during their lek courtship pageants, where up to 150 animals gather together twice a year to honk and flap and generally try to impress the females. The females are picky, though, and only a very small percentage of males are chosen for mating.

Very cool animals.

American owl cull - immoral or a necessary evil?

The US Fish and Wildlife Service plans to kill 470,000 owls, and conservation organizations are at each other's throats over it.

The department has reluctantly concluded that they need to cull nearly half a million barred owls from California, Oregon and Washington over a span of some three decades. This is because the native northern spotted owl is becoming increasingly endangered in the region, partly because of human-driven habitat destruction (mainly logging activities), but partly because the barred owls - originally native to the Eastern United States, and NOT endangered - are much more adaptable and are moving into traditional northern spotted territory in the West.

Critics of the proposal argue that the plan is impractical, reckless and ethically questionable. But without it, the northern spotted owl may well go extinct. So, what to do? Well we could maybe stop the logging of old growth forest for starters, no?

Managed dog hunts of coyotes making a comeback

I had no idea that coyote hunting as a "sport" even existed, but apparently the government of Ontario (yes, them again!) has seen fit to expand a licensing regime that allows such things.

The so-called "train and trial" licenses are for dog hunting clubs where coyotes are caught in the wild and enclosed in a fenced area, and where hunting dogs are let loose on them, supposedly so they can learn to hunt such wild animals (why?) and to hone their hunting skills. Judges score the dogs on their hunting prowess, award points, and crown champions at meets. 

It sound to me like the next thing to dog-fighting and bear-baiting, but apparently it's legal, and the Ford Conservative government is even encouraging it, after previous administrations have played it down somewhat. 

The Ontario Sporting Dog Association insists that no animal is hurt in the sport - well, of course they do! - and the government obviously prefers this line. Others, though, beg to differ, claiming that coyotes have been hurt and killed by dogs, and that a coyote trade ring exists where coyotes are captured, kept in inhumane conditions, and then sold off to these train and trial clubs.

Doesn't seem like the kind of thing our elected representatives should be condoning or encouraging.

How to save the northern white rhino

I knew that the white rhinoceros was an endangered species, teetering on the edge of extinction. What I hadn't realized was that there were two subspecies - northern and southern - and that the northern white rhino was substantially more endangered than the southern.

In fact, there are only two northern white rhinos left alive anywhere in the world. Unfortunately, both of them are female: a 35-year old mother, Najin, and her 24-year old daughter, Fatu. The last male of the subspecies, Sudan, died back in 2018. Najin and Fatu are living the good life in Ol Pejeta Conservancy in Kenya, cared for around the clock and protected by armed guards. But the last two animals being females sounds like the end of the road, right?

Well, maybe not. The southern white rhino population is not exactly healthy, but they do at least number around 20,000 now, thanks to strong protection measures, captive breeding programs and, most recently, a surprisingly successful IVF (in vitro fertilization) program.

Unfortunately, for medical reasons, neither Najin nor Fatu are able to actually give birth. But the thought is that southern white rhinos are probably sufficiently similar to their northern cousins for a southern surrogate mother to bear a northern baby. An outfit called BioRescue has been creating northern white rhino embryos from Fatu's eggs and frozen sperm collected from other males before they were eradicated. The plan is to use southern surrogate mothers to host these northern embryos.

Northern white rhinos typically live to about 40 years of age, so there is a small window of opportunity to allow the two remaining animals to raise a few babies and teach them the social behaviour of their kind, but time is now of the essence. 

It's an audacious and slightly desperate plan, but these are desperate times for the northern white rhino.