Cozumel

The Island of Cozumel lies a mere 20km off the east coast of the Yucatan Peninsula and is only 45km by 15km in size. There are mangroves around the island's coast but the habitat is mostly "semi-humid" scrub, a fascinating tropical habitat type that does not grow particularly tall despite receiving reasonable quantities of water (rainfall). This habitat type is also found in the eastern Yucatan Peninsula.


The theory of island biogeography would predict that such an island have moderate biodiversity, limited by its small size but augmented by frequent arrivals from the mainland. Cozumel, however, is something of an enigma, since it has four endemic species and many distinctive endemic subspecies, perhaps surprising given its proximity to the mainland. The avifaunal mixture of Cozumel is also intriguing in that, although it shares some species with the mainland, there are a suite of species with a more Caribbean distribution, including for example the Western Spindalis that occurs on Cozumel but not on the mainland. Other bird like Yucatan (Yellow-lored) Parrots and White-crowned Pigeons don't mind making the crossing on a regular basis, apparently even twice daily in some seasons.

The four Cozumel endemic species include a hummingbird, a vireo, a thrasher and a wren. The hummer is the Cozumel Emerald, and what a beauty! Unfortunately, the long, deeply forked tail of the male doesn’t show very well in these photos... but you get the picture!


The Cozumel Vireo is very distinctive. This species spends most of their time skulking in the scrub and is not easy to see well.

I didn’t manage photos of the other two endemics – the skulking Cozumel Wren – basically a House Wren who probably took a liking to island living and decided they didn’t feel like traveling back north... well, at least migration suspension seems like the most plausible explanation (or maybe they discovered Tequila?). The fourth endemic, the Cozumel Thrasher, is now feared extinct. Apparently they were common until the hurricane in September 1988. Since then there have been very few sightings and it seems as though this species will not recover. Many other local breeding species took a hit in that hurricane but they have since recovered. Perhaps there was something unusual about the thrasher or perhaps there was a cocktail of factors with the hurricane being the last straw… we may never know!

Cozumel is also a good place to see some of the Yucatan Peninsula endemics. The Yucatan Vireo is an inch or more larger than the Cozumel Vireo, with a much larger bill and with a global range that is restricted to the eastern portion of the Yucatan Peninsula and islands, being found in the characteristic semi-humid tropical scrub habitat of the region and also in mangroves. As it turns out, Cozumel was the only place I saw Yucatan Vireo. Note how thick the supercilium is on this species.

Another Yucatan endemic that seems easier to see on Cozumel than elsewhere is the Yucatan Woodpecker. In most sites in the Yucatan the much larger Golden-fronted Woodpecker is easier to see than the endemic Yucatan Woodpecker, but on Cozumel the converse was true! Note the yellow nasal tuft on this species, one of the features that separate them from Golden-fronted Woodpecker. According to Howell the yellow should extend underneath the bill but that didn’t really seem to be the case with the Cozumel birds… anyone care to comment?

Yet another Yucatan endemic, the Black Catbird, skulks around in the shrub layer, sometimes coinciding with overwintering Gray Catbirds. Once again, this species was easier to see on Cozumel than most sites on the mainland.

Then there are those Cozumel endemic subspecies. On Cozumel endemic rufivertex subspecies of Yellow Warbler has a rufous crown, although in this photo the crown is not so easy to see. Migrant Yellow Warblers from the north also occur.

The caboti subspecies of Bananaquit is only found only Cozumel and a tiny portion of the northeasternmost corner of the Yucatan Peninsula. Their range is very disjunct from the mexicana subspecies which you can see in Belize, northeastern Guatemala, Chiapas and the southernmost parts of Veracruz and Oaxaca. The caboti subspecies of Bananaquit is larger and has a white throat as opposed to the grey throat of mexicana.

Cozumel’s endemic intermedia subspecies of Yellow-faced Grassquit has less black on the chest than mainland races.

Cozumel is the only place is Mexico to see the stunning Western Spindalis, formerly known as Stripe-headed Tanager. This species occurs on many Caribbean Islands and of course is a highly sought-after rarity in Florida. The first photos shows the vibrant colours of the male – a very cooperative little chap who popped up in front of me at eye level. The second photo shows the female enjoying a feast!

Other Cozumel residents with a Caribbean affiliation include the Caribbean Elaenia, found on offshore islands and the eastern most portion of the Yucatan peninsula. Like many flycatchers in this group this species is not easy to identify from other similar species; however, their bright orange lower mandible is a particularly noticable and recognizable feature.

The Caribbean Dove has a somewhat similar distribution to the Caribbean Elaenia; however, their range extend much further westward and also further south in the Caribbean Island chain. Not easy to tell from White-tipped Dove, but their grey, as opposed to vinaceous, crown is a good feature.

Cozumel also has its share of species with more widespread distributions. One of these is the handsome Mangrove Cuckoo. In my experience, Cozumel is the easiest place there is to see this skulker, which is notoriously difficult to find through much of their range. On Cozumel, this species is not confined to mangroves and I saw them in fruiting trees and also in semi-humid scrub.

The Bright-rumped Attila is a widespread flycatcher, ranging from Mexico to Brazil. This one popped up for me and gave good views for a minute or so. Note the hooked bill shape.

Tropical Mockingbird is also wide ranging, although, unlike most of the species covered in this post, they are easy to see anywhere in their range.

Cozumel also attracts its share of Nearctic breeding migrants, including a good selection of shorebirds like the beautiful Black-bellied Plover (American English) or Grey Plover (British English) or Silver Plover (me!).

Another migrant, a Sora, strolls around on some exposed mud. I don’t often see Sora this well up here on their breeding grounds!

And a Palm Warbler forages in the leaf litter… In a few short months, I will be surveying for this species and other boreal breeders as part of the Manitoba Breeding Bird Atlas… but they are content to stay on Cozumel for now!

Another familiar face – indeed a familiar masked face, Raccoons are resident on Cozumel. Like here in North America they are not shy about feeding on human garbage. On the other hand, there is no need to sleep away the winter months down on Cozumel!

More to come soon… but first, better go shovel that fresh snow!

Neotropical owls

Back recently from a trip to Mexico, Belize and Guatemala, which I will post about in more detail soon. Since I haven’t posted anything in nearly a month, I thought I would start quickly by sharing photos of some of the nightbirds from this trip. I put together and more comprehensive and organized series in due course.

We start with my lifer Crested Owl. This phenomenal looking creature is quite unique and placed in their own genus Lophostrix. Their voice is also rather unique, being exceptionally gruff, even for a large owl. I have wanted to see Crested Owl for a long time so on this trip, whenever I found myself in lowland rainforest, I spent my nights looking for this species. It wasn’t until near the end of my trip, at Palenque in Mexico (famous Mayan ruins) that I finally caught up with this enigmatic species. I had been birding in the ruins and then birded back down the entrance road very slowly after dark. After hearing a Crested Owl call it took nearly half an hour to track the caller down, so I was absolutely elated when I was able to maneuver into position to take this photo. Of course when I walked passed the military check point, they searched my persons and my backpack thoroughly (in case I had tried to smuggle out a relic) and not me I was not supposed to be on the road after dark (the people at the ticket counter had told me this was allowed). At that point, I didn’t mind the incursion – I already had my photos of Crested Owl.


Another highlight was this Bearded Screech-Owl at the Pronatura Reserve called Huitepec, near San Cristobal de las Casas in Chiapas, Mexico. It took three nights to find this species. On the first two, the wind picked up an hour before dusk and made listening for owls almost impossible. On the third night it looked like it would rain but instead the blanket of cloud and fog seemed to hold back the wind. As a result I got my lifer Bearded Screech-Owl and Unspotted Saw-whet Owl, although I didn’t manage a photo of the latter. The Bearded Screech-Owl, like many screech-owls in dichromatic, i.e. there are two colour morphs, red and grey. This bird is obviously a red morph individual. Notice also the long wings relative to the tail and the naked (unfeathered) toes characteristic of this species.

Of the Strix owls (large and round-headed) in the tropics, Mottled Owl is the most ubiquitous, being found from Mexico to Argentina and from the lowlands up to 2500m asl. I photographed this species at four sites on this trip. This photo was also taken at Huitepec on the same night as the Bearded Screech-Owl above.

The Black-and-white Owl was formerly placed in the genus Ciccaba but now merged into Strix (there has been a fair bit of merging of genera in owl taxonomy recently). Unlike the Mottled Owl however, this species sticks mostly to the lowlands. I took this photo at Cockscomb in Belize, a wonderful lowlands rainforest area.


Like the Mottled Owl, the Ridgway’s Pygmy-Owl is widespread and common. This species used to be called the Ferruginous Pygmy-Owl (and still is by the AOU) but the North/central American form (Ridgway’s) is now considered specifically distinct from the South American form (Ferruginous). I heard and saw this species at quite a few sites on this trip. This photo was taken at the ruins at Cobá.

Not an owl, but another exciting nightbird is the Northern Potoo. The potoos are a Neotropical family of nocturnal insectivores. It is amazing to watch such large birds sally forth from a perch in the night to pluck an insect from the air, like a huge nocturnal flycatcher. Their superb camouflage makes them difficult to find while roosting (almost completely motionless) in the daytime. In this case, I heard this bird calling just before dawn and followed them to their roost.

Well, this is a sampler but plenty more to come soon. I will also update my webpage http://artusophotos.com/ soon. There are larger versions of the above photos available at http://artusophotos.com/3_Nightbirds/index.htm

drinking snow

Did you mother ever tell you not to drink snow? Well, apparently their mothers did not tell these birds… These hardy birds presumably don’t have to worry too much about lowering their body’s core temperature by taking a little snow, and if your diet is dry like seeds (or the fruit you’ve been eating is dry and shriveled) then a little water is very important to aid digestion...

Cedar Waxwing

Red Crossbill - female

Red Crossbill - male

Ruffed Grouse

These Red Crossbills and Ruffed Grouse are both drinking snow that has accumulated on a branch and has perhaps been compacted or melted a little and refrozen to ice, in which case it will have more water content that powdered snow…

Birds and climate change and, well, change...

There is an interesting little summary piece on the Birdlife International page today about the impact on birds of climate change. You can read this at: http://www.birdlife.org/news/news/2009/12/climate_impacts.html

Here in Manitoba, we have seen northward shifts in particular of aspen parkland species. For example, I recently documented Yellow-throated Vireo in the Porcupine Mountains, a good 200km north of even the most current range maps. In and around The Pas, where land clearing for agriculture has created parkland like habitat, other parkland species like Black-billed Cuckoo are starting to show up, again well north of their expected range. Trembling aspens themselves are apparently growing faster and are encroaching on new areas at a rapid rate.

Notice anything special about the bird in the photo below?


You might if you had been studying them in the U.K since the 1960s! This is Blackcap, a type of Old World warbler. Since the 1960s some Blackcaps breeding in Germany, began changing their migration. Instead of going southwest to Spain, they went northwest to southern England. There have been many articles written about that fascinating phenomenon. It is also one of those cases that demonstrate the important partnership between birdwatchers and scientists. It is precisely because there are so many birdwatchers in every corner of the British Isles that this phenomenon was so well documented. But the story doesn't end there...

We are also starting to learn of the truly staggering pace at which birds can react to seemingly subtle changes in their environment. An interesting piece came out in the Globe and Mail summarising the findings of a recent study demonstrating how the population of Blackcaps that migrate to the U.K have made subtle changes to their bill shape and wing shape in just a few decades. The authors concluded that this was thanks to the combined effects of climate change and… wait for it... bird feeders! Really makes one think of the impact of even seemingly innocuous behaviour like putting up a bird feeder. Read the following for more details: http://www.theglobeandmail.com/news/technology/science/british-birds-rapid-evolution-signals-human-impact/article1387804/

It is amazing what a difference a few degrees makes… and the cumulative pressures on birds from so much and so many types of change, change, change is staggering!

Another one on the wrong list!

With the announcement today of the latest round of COSEWIC (Committee On the Status of Endangered Wildlife in Canada) assessments, Manitoba has gained yet another bird on the wrong list – the list of threatened species. And, not surprisingly the newly listed species is a grassland bird – the grassland specialist being probably the most threatened group of birds by habitat, at least in North America.

The species in question is the Chestnut-collared Longspur, a species that breeds in our native prairie (in Canada in Alberta, Saskatchewan and Manitoba). The species has suffered severe population declines since the 1960’s. Like so many grassland birds, the Chestnut-collared Longspur is threatened by loss and fragmentation of native grasslands from the usual array of anthropogenic developments and their influences on the landscape.

More details on this new round of assessments can be found at http://www.cosewic.gc.ca/eng/sct0/index_e.cfm?#results

A few photos of the Chestnut-collared Longspur in community pastures with native hay in western Manitoba are included below. You can appreciate the rich colours of this well marked species but you will also notice in the first photo how the cryptic patterning on the back works well as camouflage in the grasslands. In the second and third photo you can see the elongated toes that gives the four species in the genus Calcarius their English name (longspurs). In Manitoba this species once bred as far east as Winnipeg, including at sites near the present day airport. Unfortunately, this species has not only declined in our province but also has experienced a dramatic collapse of the periphery of their range. These days, you need to go almost all the way to the Saskatchewan border to see one (at least to the Brandon area anyway). The same is true for other grassland specialists like Baird’s Sparrow, Burrowing Owl and Sprague’s Pipit. These birds are in urgent need of our assistance to try and win back the prairies that we are losing at such as alarming rate!

Borneo - waterside

One of the best ways to see wildlife in the rainforest is to use the waterways – their openness creates light and allows one to see into the canopy. I was able to get out on the water along the magnificent Sungai Kinabatangan (Sungai means River) and in a few other places near the coast.

One of the most remarkable species that lives along these waterways is the Proboscis Monkey. The large nose of the male that gives this species their name acts as a resonating chamber when they issue their warning calls. The fat belly is a product of a complicated stomach specialized bacteria to digest the leaves that make up their diet (leaves that would be unpalatable to most).

The Estuarine Crocodile loiters along the banks of the Kinabatangan and with a bit of luck can be seen sun baking.

The Bearded Pig is another resident of the riverside forests, where there are plenty of opportunities for wallowing.


The Oriental Darter, the Asian member of the Anhinga family, is very difficult to see on the Asian mainland, where it has become very rare. Borneo is one of the best places to see them!


With views of the canopy all around you, traveling the river by canoe is a great way to see hornbills. These are Sunda Wrinkled Hornbills and there is a pair of Oriental Pied Hornbills also near the bottom of the photo.


Away from the main river where there are smaller pools or wetlands there are of course various members of the rail family. This is the shy Red-legged Crake.


And on smaller forest streams, one of the distinctive Asian groups, the forktails, related to robins, make their living. This is a female Chestnut-naped Forktail. The females have more chestnut on the back than the males! This individual seems to have less of a forked tail than most, perhaps due to wear…


The Straw-headed Bulbul is most commonly found in riverside forests. This beautiful songster is now listed as “Vulnerable” (one step down from Endangered), primarily due to declines caused by trapping for the cage-bird industry and also habitat clearing. This species has disappeared from many areas where they were very common a few decades ago. They are virtually extinct on Sumatra, where trapping of live birds is rampant, but fortunately they still occur in places like Borneo. I can recall several times hearing their magnificent song coming from a cage, which I found completely depressing.


There are pittas to be found near the water too. The beautiful Mangrove Pitta, one of several pitta species with a similar rainbow colour scheme, is restricted to the coastal Mangroves and is threatened by the heavy deforestation of that habitat type.


The Hooded Pitta is another species that I saw along the waterside…

Naturally, there are kingfishers by the river (as well as deep in the forest). The well-named Stork-billed Kingfisher, with their enormous bill, is one such species.

The much smaller Blue-eared Kingfisher with their magnificent rich azure, neon and red is a sight to behold. Here are two images to show the richness of bother the upperparts and the underparts of this bird.



That’s it for this small series. Only a small sample of the avian beauty of the area. More photos from South East Asia at http://artusophotos.com/

Borneo - Danum Valley 2

There are more than just birds in the rainforest canopy. While walking a long trail at Danum I came around a bend only to face this male Bornean Orangutan feeding in a fruit tree. He immediately climbed higher and began to sound as threatening as he possible could. Of course I tried a few photos but when he started breaking off small branches and throwing them at me I had to leave him alone. Apparently female Orangutans in this situation prefer to throw their own excrement at you – an even more effective strategy I guess. Not so long ago, most people considered the Orangutan to be a single species endemic to Borneo and Sumatra. These days most taxonomist recognise two genetically distinct species, the Bornean Orangutan Pongo pygmaeus now listed as Endangered, their population having fallen by more than half over the last 60 years, and the Sumatran Orangutan Pongo abelii, listed as Critically Endangered, their population being reduced to less than a quarter of their numbers 75 years ago.



The Colugo, or “Flying lemur” is a nocturnal animal (not actually related to lemurs) with a large membrane between their limbs that enables them to glide considerable distances between trees. I surprised this one in the daytime while moving through the bush after a calling pitta. You can see the membrane and the large eyes.



I always spend a fair bit of time out at night if I possibly can and there were many nocturnal species to keep me busy at Danum. The Buffy Fish Owl, a stunningly beautiful owl in my opinion, likes to hang around the light of the research station and is easier seen here that anywhere else I know. Relatives of the “horned owls” (Great Horned Owl and Magellanic Horned Owl) and eagle-owls, the Asian fish-owls are very adept at catching fish in shallow water.


The Buffy Fish Owl’s relative, the Barred Eagle-Owl is a secretive denizen of the rainforest.

The Brown Wood Owl is in the genus Strix, a genus familiar to North American and Europeans. A pair hang around the camp ground at Danum, although I must admit that I am cheating because I did not take this photo there.

The Brown Hawk-Owl (or Brown Boobook) is not related to the Northern Hawk-Owl. This species belongs to primarily Australasian genus Ninox, often referred to as “Boobooks” (an Australian onomatopoeic word). Many authors have split this species into different species (Northern Boobook Ninox japonica, Brown Boobook Ninox scutulata and Chocolate Boobook Ninox randi) In Southeast Asia the Brown boobook is nicknamed the “doo-up” bird because of their two note inflected song. There is the resident form Ninox scutulata borneensis on Borneo and also the migratory japonica form in winter.

The frogmouths are a fascinating nocturnal group related to nightjars but with a much more vertical posture. Their New World relatives are the potoos. Their enormous gape and sensitive rictal bristles are an adaptation to capturing nocturnal insects on the wing. This is a Large Frogmouth, the largest Asian species and possibly the most difficult to see. I organized a special night drive to find this bird to an area where one had been heard previously. I was well worth the long drive as this is the only occasion I have seen this species.

Back in the light of day – well what little of it reaches the lower storey of the forest — there are gems to be found low down too. This diminutive Black-backed Kingfisher (<14cm>

The Little Spiderhunter probes for insects with their long bill, that also allows them to feed on nectar.

The magnificent trogon family is well represented on Borneo, and many of them are surprisingly low down in the canopy. This male Scarlet-rumped Trogon is just a few feet off the forest floor.

Likewise, this juvenile Red-naped Trogon hides low down. The second image shows an adult male.

Perhaps the most highly sough after gem of the Asian forest floor is the pitta family. Super secretive with electric colours, they capture the attention of all birders in the region. The superb Black-and-crimson Pitta has a colour scheme of electric red and neon blue on the back.

The Banded Pitta is like a living rainbow. They are shy though and hard to capture their magnificence on film. Some people have split this species into several species on the various Sundaic islands and the Thai-Malay Peninsula.

The Blue-head Pitta is a dazzling Bornean endemic… they are like a ball of blue light hopping along the dark forest floor!

The pheasants are another Asian-centered group that are superbly plumaged but difficult to see. One of the most sought after species is the Great Argus – a large cryptically patterned pheasant with tail feathers nearly a metre and a half long and elongated secondary feathers that are more than a metre long that are used in a spectacular display. Unfortunately for me, the only photo I ever managed of this secretive bird was this male slinking away in the undergrowth and barely visible despite his enormous size.

Also on the ground, the endemic Bornean Wren-Babbler, may not be colourful but their cryptic pattern is also beautiful and they are just as secretive as pittas and pheasants.

Another one of those shy Asian babbler, the Chestnut-backed Scimitar Babbler pops out in front of me briefly.

While back on the ground, this Black-capped Babbler, slinks around a tree trying to avoid detection.

While this Emerald Dove tried to remain undetected by sitting tight. In the darkness of hte forest floor their bright plumage is somewhat obscured, as is true of so many of the Asian forest gems.