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Turtle Nesting Season

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This is the time of year when the Olive Ridley Turtles (Lepidochelys olivacea) come ashore to lay their eggs. Here in the beaches around San Carlos they do not nest in large numbers, so there is no turtle-watching tourism, but it seems the number of nests is increasing.

The turtles hang around near the nesting sites, feeding and mating for about two months before the females come ashore to lay their eggs, so there is always a chance you will see one while snorkeling or paddling quietly around local waters.

Olive Ridleys aren’t big, as sea turtles go, about 60 cm or two feet in shell length, so watch for a head about the size of a fist, poking out of the water. When they come up for air they stick their heads above the surface several times, gulping air, before they submerge. Once they go down, they may remain submerged as long as several hours, depending on how active they are.

All sea turtle species are in danger of extinction, mostly due to human harvesting of the eggs and adult turtles. Olive Ridleys are actually the most abundant sea turtle, worldwide, but are still listed as vulnerable  by the International Union for Conservation of Nature (IUCN). There is an international treaty called the Convention on Trade in Endangered Species, commonly known as CITES. Under this treaty, of which Mexico, Canada and the USA are all signatories,  the trade in listed species of plants and animals, and any parts, including a shell you may find on the beach or in a market is strictly controlled. Taking a sea turtle or even a piece of a shell across the border into the U.S. or Canada will land you in very hot water, and may result in heavy fines or even jail time.

Once they reach maturity,  these turtles nest annually, typically in large numbers called arribatas. Here in San Carlos, the turtles are so few in numbers that nesting occurs singly. Turtle mortality is highest in the egg stage. Nests sometimes drown in extra-high tides, can be exposed by beach erosion from storms, or be dug up by egg predators such as raccoons, coyotes or feral dogs.

The eggs hatch after about two months incubation, usually at night. The newly-hatched young dig their way to the surface, and head to the sea, guided by moonlight sparkling of the surface. They have to get into the water before first light. If they are caught out in the open, they are quickly gobbled up by vultures, frigatebirds, gulls and ravens.

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Annette Felix is a local woman who is spearheading a campaign to protect these wonders of nature. She has organised support to patrol the beaches, looking for tracks or any evidence of nest-building. She has also recently put together a flyer warning people of the possibility of nests on the beach, and suggesting things they can do and should not do, in order to maximise the survival of eggs and hatchlings.

Because the eggs are just under the surface of the sand, they can be crushed by a careless pedestrian or under the wheels of an ATV or truck. Motorised vehicles are banned by law from the beaches here, but this rule is poorly enforced and often ignored. So the first rule is; be careful where you walk, and try to discourage motorists from using the beach as a racetrack.

When the hatchlings emerge, they may be misdirected by lights from homes and streets, and head away from the sea. By the time they realise their mistake, they are a long way from the sea and are vulnerable to predators. So the next rule is: lights out. Keeping exterior lighting to a minimum is crucial to the survival of hatchlings.

These animals are adapted to swim in the sea and are very good at it. But travelling overland is a tiring and difficult venture for a female turtle carrying a heavy load of eggs. Beached boats, chairs, trash and even sand castles and pits dug in the sand by happy children can be a serious impediment to females and also to the hatchlings heading for the sea. So the next rule is: keep the beach clean and free of trash and obstacles. Fill in your pits and flatten your sand castles when you are finished with them.

Following these simple rules will contribute to turtle conservation, and help to ensure that these magnificent animals which have been on the earth for millions of years, will still be here for your grandchildren to see and enjoy.

Photos from National Geographic.

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First Rain Part II: a Moveable Feast

I am sitting outside in the early morning of a cloudy day, after a long, soaking rain that lasted through the night. Swarms of termites hover over the ground and crawl along the wall.  A gecko, normally strictly nocturnal,  is dashing from the cover of a window frame  to  take advantage of this sudden abundance. It seems to know they will be gone soon and this rich feast is too much to ignore, even at the risk of being eaten himself.

Termites are social insects with a caste system. Each colony will have a king and a queen. The queen grows a huge abdomen and pumps out thousands of eggs. The eggs hatch and are divided into workers, soldiers and winged reproductives called alates. The alates have been waiting for the rain.

Termites are essential members of the desert ecosystem. Living underground by the millions, they take the energy and nutrients from dead and decaying vegetable material and redistribute it down into the soil. They do not have a waterproof skin, so they remain underground or build inverted tunnels of chewed cellulose and saliva along the surface of dead grass, sticks and hard surfaces like cement. In this way they search for food without exposing themselves to the dry air.  But after a rain, they take advantage of the humidity to spread farther and faster than tunneling would ever allow. Great swarms of alates take to the air, hoping to find a mate and settle on the ground, look for some wood to chew into and start a new colony. Most don’t make it.

The mating swarm of termites is a rich source of food for many desert animals. Bats, dragonflies and birds snatch them from the air. On the ground they are gobbled up by toads, lizards, snakes, mice, skunks, coatis, more birds and a variety of invertebrates such as ant lions, scorpions and spiders. And the timing couldn’t be more perfect.

This sudden burst of available protein and energy will fuel the mad dash that high temperatures, and abundant moisture and sunlight will bring to the desert. For it won’t be long before the ponds dry, the soil bakes hard again, and most life will shut down or go underground until the rains come again, many months from now.

 

 

The Desert Responds to its First Rain: Part 1

The thunderstorm came in just after sunset. Temporarily blinded by a nearby bolt of lightning, I can feel the thunder in my chest. Quickly the storm moves on and the air is filled with a new sound: the calling of thousands of toads. I am standing outside a room at the Posada, with Matt and Richard, two American conservationists spending the night, and sharing their beer with me.

We wander down to a newly-created pond, drawn by the mating calls of Couch’s spadefoot toads, Scaphiopus couchii . Already they are pairing up, the males embracing the females from behind. Soon eggs will be laid, fertilised and left to fend for themselves in a pond which will completely dry up in less than two weeks.

I remember the calls of frogs and toads from my childhood in Northern Ontario. Each species would have its own season, throughout the spring and summer months, and I could hear the calls from my bedroom window.

So imagine my surprise when the very next night, I went down to the pond to listen to the toads and was met with silence. Northern frogs time their mating by temperature and day-length, and call for weeks before all are mated. But in the desert, the ponds dry up, and so the tadpoles have a short time to grow and transform into adult toads.

The mating was over that first night, and already the eggs were hatching into tiny tadpoles. The adult toads have a few days to feed before the ground starts to harden, and they burrow in again to await the next rains.

Nacapule Canyon

San Carlos is located near the southern edge of the Sonoran Desert, but it hasn’t always been desert. During periods of a wetter climate, this area was a part of the Tropical Deciduous Forest. As the climate dried again, the Tropical Deciduous Forest retreated to the south, and was replaced with the desert vegetation we see today. There remain, however, a few places where the tropical forest species survive.

The Nacapule Canyon is one such place. A deep, narrow gap carved into in the surrounding hills, the Nacapule Canyon is shaded much of the day, which reduces evaporation. Much of the surrounding rock is porous volcanic ash, which absorbs the rain and slowly releases it to the bottom of the canyon. The result is an oasis, where tropical deciduous forest trees and shrubs can survive, completely surrounded by desert.

The entrance to the canyon is a broad trail, an easy hike up the arroyo. The walls of the canyon are made up of layers of red, yellow and grey rock twisted and carved into weird and beautiful patterns. A short zipline crosses overhead, accessible by climbing a short, steep trail. The trail follows the arroyo, sometimes running alongside, where the arroyo is filled with boulders. As you follow the gentle slope upwards, you come to the tree from which the canyon is named, a Canyon or Macapule Fig. There was an even larger specimen nearby, but it was wiped out by the terrible rains of a hurricane.

The canyon splits here, one branch following the edge of a permanent stream, to the right, the other, a dry arroyo straight ahead. Neither branch goes very far, so there is time to explore both. The right fork becomes thick with vegetation as it follows a small permanent stream and wanders through a thicket of palm trees. After the palm trees, the way gets steep, and there is a small cave to explore, or to travel through as you start to climb. Climbing higher brings you to a larger cave, some small ponds and eventually you come out on top, and the trail descends to the desert to the north of the canyon. Rather than descend, if you got this far, you can turn around and head back to the fork

Following the second fork, brings you to a dry waterfall below a series of plunge-pools. There is a rope ladder on the right which brings you to the top of the falls. From here you can see more pools, glistening black in the sunlight. There is even a Nacapule Canyon leopard frog here, if you can spot it. Can you imagine a frog in such an isolated place surrounded by desert?

The Nacapule Canyon is a jewel in the desert, a place to explore, or just to spend a moment of peace.

Summer Monsoon

It’s night, about an hour after sunset. The fluffy clouds of the afternoon have congealed into a solid mass of blackness, blocking out the stars. Yet all is not dark. There are flashes beyond the hills, several every second, coming more frequently as the minutes pass.

While the sun was up the humidity was quite bearable. Now that the sun has set, the air has become so saturated that the sweat glistens on my skin and soaks my clothes, refusing to evaporate. This is the summer monsoon.

When we hear the word “monsoon” we may think of a tropical forest, of swollen, muddy rivers, of flooded roads, of hot, humid nights alive with the buzzing of insects and the drumming of rain on tin roofs. In some parts of the world, that is a pretty accurate picture. But, despite what many people from the American Southwest are led to believe,  monsoon is not rain. You hear up in Tucson, “We had a real monsoon last night, I’ll tell ya.” They get that from the phrase “monsoon rain”. The fact the word “rain” is in the phrase should tell you that monsoon is not a type of rain. You don’t hear people talk of “thunderstorm rain” or “heavy shower rain”; that would be redundant.

So what is monsoon then? The word comes from the  Arabic, mawsim, meaning “season”. The monsoon is a seasonal wind-driven weather pattern, which brings dry weather during the winter, and wet weather in the summer. The Indian sub-continent and SE Asia all the way to N Australia are all affected by this weather pattern, as is West Africa and the W coasts of the Americas.

This seasonal shift is what gives it the name monsoon, but the wind pattern is nothing more than a sea breeze on a very large scale. Here in Sonora, the desert heats up in the summer faster than the water from the Gulf of California. The hot, desert air rises, leaving low pressure behind, which is filled in by the cooler air from the sea. As this cooler (not exactly cold), humid air moves inland it is pushed upward over local mountain ranges. As the air rises, two things happen. The air becomes over-saturated with moisture and forms tall clouds with growing tops. And the ascending clouds generate static electricity. This build-up becomes too much for the cloud, and a thunderstorm is the result.

Even the hardiest desert shrub needs rain. All through the winter and spring the desert has become drier and drier. The hill-sides are rock and gravel, with a sparse cover of bunches of sere, grey twigs, and the occasional cactus.standing in green defiance. The arrival of the monsoon has been a cruel joke to this tough vegetation. Hot humid air gives no relief and the nightly show of distant lightning does nothing to quench a desperate thirst.

As the monsoon progresses, the storms have grown in size and approached a little closer every night. Some nights they are close enough to hear the thunder (typically less than about 11 miles or about 18 km), and we may even get a spatter of raindrops that glue the dust to the windshield on my pickup without being quite enough to join together and wash the dust away. So we wait. It will come eventually. It must.

And it finally does. Lightning blindly stabs the ground with its crooked spear, shaking the heavens and the earth with great booms of thunder that roll around the hills, blending one with the next in a continuous rumble like the march of an army of giants. The still, moist air is suddenly pushed aside by a strong breeze and you can hear the rain approach. It comes as a wall, pouring from the sky in a solid mass of water, momentarily almost drowning out the sound of thunder.

Soon both thunder and rain abate slightly, and during the flashes of light, one can see that the road has been turned into a creek, the middle washing away down the street, leaving a deep, stony gash where a dirt road used to be. Nothing can be done about it, so we watch the storm and celebrate.

 

 

 

 

 

Nacapule Canyon

San Carlos is located near the southern edge of the Sonoran Desert, but it hasn’t always been desert. During periods of a wetter climate, this area was a part of the Tropical Deciduous Forest. As the climate dried again, the Tropical Deciduous Forest retreated to the south, and was replaced with the desert vegetation we see today. There remain, however, a few places where the tropical forest species survive.

The Nacapule Canyon is one such place. A deep, narrow gap carved into in the surrounding hills, the Nacapule Canyon is shaded much of the day, which reduces evaporation. Much of the surrounding rock is porous volcanic ash, which absorbs the rain and slowly releases it to the bottom of the canyon. The result is an oasis, where tropical deciduous forest trees and shrubs can survive, completely surrounded by desert.

The entrance to the canyon is a broad trail, an easy hike up the arroyo. The walls of the canyon are made up of layers of red, yellow and grey rock twisted and carved into weird and beautiful patterns. A short zipline crosses overhead, accessible by climbing a short, steep trail. The trail follows the arroyo, sometimes running alongside, where the arroyo is filled with boulders. As you follow the gentle slope upwards, you come to the tree from which the canyon is named, a Macapule Fig. There was an even larger specimen nearby, but it was wiped out by the terrible rains of a hurricane.

The canyon splits here, one branch following the edge of a permanent stream, to the right, the other, a dry arroyo straight ahead. Neither branch goes very far, so there is time to explore both. The right fork becomes thick with vegetation as it follows a small permanent stream and wanders through a thicket of palm trees. After the palm trees, the way gets steep, and there is a small cave to explore, or to travel through as you start to climb. Climbing higher brings you to a larger cave, some small ponds and eventually you come out on top, and the trail descends to the desert to the north of the canyon. Rather than descend, if you got this far, you can turn around and head back to the fork

Following the second fork, brings you to a dry waterfall below a series of plunge-pools carved out of the rock. A rope ladder on the right brings you to the top of the falls. From here you can see more pools, glistening black in the sunlight. There is even a Nacapule Canyon leopard frog here, if you can spot it. Can you imagine a frog in such an isolated place surrounded by desert?

The Nacapule Canyon is a jewel in the desert, a place to explore, or just to spend a moment of peace.

Field Biology Course 2016

Once again my season in Belize has come and gone. The best part of my work at Half Moon Caye is the last: a group of Biology students from various Ontario universities, led by University of Western Ontario Professor Graeme Taylor, spend 11 days in camp doing a course in Field Studies.

The students have a variety of tasks to complete, starting before they even leave home. Their first task is to learn to identify a wide range of commonly-seen marine life, ranging from sponges and corals to fishes.

An aside: the plural “fish” refers to individual fish. The plural “fishes” refers to types or species of fish.

With a head start on species identification, the students were ready to go  right into the water, so they spent the next few days familiarising themselves with the various snorkel sites. A part of their course was to keep a field journal, where they could record observations, keep track of species, and generally organise their thoughts. The ultimate goal was to explore and nourish their curiosity. Unstructured, unguided observation leads to questions. Questions and further observation lead to hypotheses. Further thinking leads to ideas about how to test these hypotheses, or to determine whether they are testable, in practice or in principle. Then the real work begins.

Once the students, working in pairs, had developed a question, hypothesis, and means to test it experimentally, they began to do their data collection. They were by no means restricted to the reefs; many of the students developed projects with terrestrial, semi-terrestrial or inter-tidal organisms. Nothing on or near the island was safe from their sharp eyes and simple measuring instruments. Everything was either passively observed or measured and put back as found.

The students worked hard and were serious in their application to this course. This was no spring break, but it was fun and the students learned a few things about the nature of field work, and got a taste of the difficulties of doing science in the field.

Best of luck to you all, and thanks to Graeme and Carli for your hard work in making this happen.

 

 

 

Paddling with new friends

While at the beach, waiting for some no-show kayak clients, I chanced to meet Whitney, a grizzled old-timer with an inflatable kayak. Since I was partially blocking his access I helped him carry his boat to the water. Whitney is a very sociable character, so it was no surprise to me that he contacted me later and arranged a social gathering at the Captains’ Club. There I met Ryc and Marc. Marc is a fisherman: that is the main focus of his kayaking. I have to say it is great fun to catch fish from a kayak.

Ryc is a do-it-yourselfer. He built his own kayak, a skin-on-wood-frame Inuit-style boat. All had tales to tell, properly lubricated with cold draft beer. By the end of our session we had arranged to go for a paddle together a couple of days hence.

When the day came, Mark had to send his regrets, as he had caught a nasty bug. The rest of us met at Ryc’s camp.

I picked up Whitney at his house, and we headed to the rendezvous. Following the coast to the north of San Carlos, once you get past the hotels and gated waterfront communities, the pavement ends. The dirt road takes you to La Manga, a community of fishermen’s houses and shacks. Here you can buy shells, or things made of shells, or eat fresh seafood at one of several little restaurants. We pass through the village escorted by dogs and children on bikes.

Eventually La Manga peters out, and the road cuts into the desert until it rejoins the coast at La Manga Dos. Instead of driving into this cluster of mostly abandoned shacks, we follow the shore behind a dune that runs parallel to a long, curved beach. There, in the shelter of the dune is a modern-day version of a hobo camp.  We are greeted by a big dog, who is too shy to be friendly, and too gentle to be intimidating.

We pull up among a loose group of trailers, and get out to introduce ourselves. This is the winter camp of Ryc and Mona, and a few of their friends. In the shade of a big mesquite tree is the kitchen and dining area. Ryc and Mona bring their matching Cape Falcon home-made kayaks, and prepare to drag them over the dune to the beach. Whitney and I take one of my double kayaks to the boat launching beach at La Mange Dos. After unloading the boat, I leave Whitney with the boat and follow Rick’s van to the Soggy Peso. We leave my boat and trailer there, and return to La Manga Dos. Ryc drops me off and heads back to his camp, a scant half-kilometre away. He and Mona will paddle over to our launching point, as it is on the way.

From our launch point we could see the long, crescent-shaped beach backed by its dune, and the tiny figures of Ryc and Mona as they slid their boats into the waves. The cloudless sky was deep blue, the sea slightly darker, flecked with whitecaps. The forecast was for light, SW winds. The forecast was wrong. The breeze was building quickly from the NW, which would push us along, as we headed roughly east. As the day progressed, those waves would turn into swells. This was not to be some idyllic cruise over a glassy sea. Nor was it dangerously rough, but definitely sporting. I started to assemble our gear.

I am supposed to be a professional. Then why is it that I brought the wrong two half-paddles? We had one good paddle, but the other one was two female halves, which don’t mate together. It was not a disaster, because I can use one half-paddle, like a canoe paddle. but there was another solution. I opened the front hatch, and pulled out a three-part mast and a sail. By the time we had the sailing rig all assembled, Ryc and Mona were idling just off the beach. The wind was whistling through the rigging as we launched directly into it. as soon as we got around the point, we hoisted the sail and we were off.

It was a pleasure to watch Ryc and Mona paddle their light, nimble craft through the waves, and we had to luff up the sail once in a while to keep from getting too far ahead. We dashed along, heading for the string of islands collectively known as Deer island.

heading for Deer I

There were a few birds flying about; some blue-footed boobies and a couple of yellow-legged gulls. These birds are so common here that I paid them little heed. But something caught my attention off to the right. I saw two peregrine falcons, most likely a nesting pair. The smaller female was flying high over her mate, who stooped down to the water’s surface and snatched something osprey-style. As it rose from the water, I could see it was carrying a small grebe. The eared grebe is a common sight on the winter sea. In fact they seemed unusually abundant this year. This one must have never seen the falcon’s approach, as they are pretty quick to dive at the first sign of danger. The falcon carried his heavy load towards Deer Island, while his mate followed from high above.

Soon we were approaching Deer Island, and cut between two rocks to the shelter of the leeward side. The strong breeze and bumpy sea was left behind and, after dropping the sail, we slowly paddled the calm, clear water, ducking between emergent rocks, and poking our bows into various caves and coves. Rounding a small point we found our predator, standing on a cardon cactus, and plucking feathers from his well-earned meal.

We continued gunkholing for a while longer, then, moving away from the shelter of the island, we hoisted the sail and made a dash for shore.

gunkholing

We landed in front of the Sunset Grill, and pulled the boats above the reach of the waves. I went to the truck and got a set of wheels that Whitney uses for his boat, and after setting them up under my sturdy work-horse of a kayak, we easily wheeled it up the beach. With the boats safely nearby, it was time for a beer.

We sat in the sun, partly out of the wind, at the Soggy Peso, and drank to our new-found friendship and to a fun and successful paddle in the lovely winter sea.

post paddle celebration

Cheers,

Jack

 

 

 

 

 

 

 

Winter has arrived

I just got back from two weeks in Ontario, during which I renewed my Wilderness Advanced First Aid certification, and spent a little time with family and friends. I don’t know what possessed me to go to Ontario in November! After spending a whole summer of heat and humidity in San Carlos, I finally arranged to go north and take the course.

I was lucky. The weather was unseasonably warm for the most part, but I did manage to see snow, sleet, rain, and the cloudy, windy days typical of November. But I also had warm sunny days too, especially when I was in the south, taking my first aid course.

On my way back I flew directly from Toronto to Phoenix. I expected to have to peel layers off when I got there, but it was surprisingly cool: barely warmer than Toronto.

Back in San Carlos, the days are quite warm and the nights deliciously cool. Sea temperatures have dropped. Today the sea off the shore of San Carlos was 68F (20C). Just three weeks ago the sea was closer to 80F (27C). Although that doesn’t seem a big difference, when you consider that water steals heat from the body 25 times faster than air of the same temperature, it amounts to the difference between a leisurely snorkel and a brisk dip.

The temperature change comes not from the lower sun and cooler days of autumn, but from a shift in the wind pattern. The Summer Monsoon is a Southeast wind that blows warm, tropical surface water into the Gulf. Sea temperatures get high enough to allow one to snorkel for hours without getting chilled. As soon as the monsoon breaks, usually in October, the Northwest winds blow all that lovely, warm water back out to the Pacific, and it is immediately replaced with cooler sub-surface water. The cool water was here all along, just a little deeper than snorkeling depth.

With the cooler water comes the winter fish: sierra mackerel, bonito (a small tuna) and yellowtail (a jack) are all here chasing the schools of herring. Also after the herring are blue-footed boobies, brown pelicans (both year-round residents) and large rafts of the ever-cute eared grebe.

Now that the air is cooler and much drier, it is time to hike the canyons and hill-tops of the Sierra el Aguaje. This is a great time to live here in San Carlos.

 

 

Yahoo News Reaches New Low in Journalism: move over National Enquirer

In a modern world, we get our news from a wide variety of sources. I admit it: I am both lazy and cheap. I don’t pay for any high quality news sources, or even any moderate quality news sources. I mostly read the news items on Yahoo Canada News. and sure, it is full of celebrity crap, and other topics of which I don’t care, but hey, I just skip over them. The point is that I believe what I read, and trust the editors of Yahoo News to be telling the truth to the best of their abilities.

But this morning I was surprised to see the headline:

Edward Snowden: Aliens Are Trying To Contact Planet Earth

In case you don’t recognise the name, Edward Snowden is the man who copied thousands of secret NSA documents and revealed some of those documents showing that the US government has been illegally spying on innocent civilians on a massive scale. Snowden has been interviewed before. I found him to be intelligent and quite reasonable. but there are always rumours about what secret files he has kept. The internet is swarming with conspiracy theories, and some strange people out there have been posting stories about how the CIA has known about aliens, and Snowden has seen their secret files. But there has never been a shred of evidence offered in support of these claims. And there was never any evidence that Snowden himself has made such claims. So when i saw the above headline in Yahoo News, I thought that maybe he has been saying something about aliens. So I read the article. The quote in the article, taken from the podcast is as follows:

“So when we think about everything that we’re hearing through our satellites or everything that they’re hearing from our civilisation (if there are indeed aliens out there), all of their communications are encrypted by default.

So what we are hearing, that’s actually an alien television show or you know a phone call… is indistinguishable to us from cosmic microwave background radiation.”

Note that Snowden himself expresses the caveat : “(if there are indeed aliens out there)”. The quote from the Yahoo article wasn’t very convincing in support of the headline.  So I looked up the podcast and listened to it. Neil DeGrasse Tyson, who conducted the interview, is a justly famous astro-physicist, and explains to his audience that he is not a journalist, and so would like to have a discussion with Snowden, geek-to-geek. He keeps it light, and, in the discussion of the theories of encrypted communication, it is Tyson himself who brings up the hypothetical question of alien communications. Snowden plays along, which leads to the quote cited above. At no time does Snowden make any claim that aliens are actually trying to communicate with us. Instead, he talks about the internal communications of a hypothetically advanced civilisation, and postulates that such communications, if intercepted by earth-bound listening devices, would be indistinguishable from background radio noise.

The Yahoo News headline is a bald-faced lie, in the tradition of the worst of tabloid journalism. Shame on you Yahoo News. And shame on the idiot who put this article together. From now on I’ll be more careful of what I read: you have lost my trust.