Comparison of Campephilus and Dryocopus:

The four photos used in this collage are:
Top left: Pale-billed Woodpecker (Campephilus guatemalensis), female, Bahía Drake, Costa Rica.
Top right: Pale-billed Woodpecker (Campephilus guatemalensis), female, Playa de Oro, Colima, Mexico.
Bottom left: Lineated Woodpecker (Dryocopus lineatus), male, Río Lagartos, Yucatán, Mexico.
Bottom right: Lineated Woodpecker (Dryocopus lineatus), male, Chaparri, Lambayeque, Peru.

I have posted previously about the differences in toe structure and perching posture of woodpeckers (see: http://artusobirds.blogspot.ca/2015/01/why-woodpecker-lost-toe.html); however a recent photo opportunity in Costa Rica reminded me that I now have a chance to comment further on the postural differences between two of the largest woodpecker genera: Campephilus and Dryocopus.

Pale-billed Woodpecker and Lineated Woodpecker are quite similar in appearance and most people look to the facial markings to distinguish them. If the head is turned away or you don’t have a good look at the facial markings there is one quick aspect of GISS (general impression, shape and size) that helps distinguish them and it relates to a major difference between the Campephilus and Dryocopus woodpeckers (and one that helps us understand why such similar looking woodpeckers belong to different genera).

The Campephilus woodpeckers include many of the world’s largest woodpecker species and they have a neat trick to support their weight and large bodies. In addition to gripping with their toes and stiffened tail feathers, they also spread their trasometatarsus wide with the joint resting against the trunk as an extra support. The top two photos of a Pale-billed Woodpecker shows how this works on a vertical trunk (top left) and an angled branch (top right). Notice how the tarsus and “joint” rest against the trunk such that the bird appears to be resting on them (which many of us might think of this joint as a bird’s knee but it is technically the ankle). Even though the Dryocopus woodpeckers are almost as large, they perch in a more “normal” woodpecker fashion, gripping with their toes and using their tail as a brace as these Lineated Woodpeckers show on a vertical trunk (bottom left) and on an angled branch (bottom right). In each case, notice how the joint does not touch the tree and the tarsi are held at more of a 45 degree angle to the body and to the surface they are resting on (as opposed to resting on the surface as in the Pale-billed Woodpecker examples). This difference is visible from a distance and can be a useful identification clue in situations where lighting or distance makes it hard to observe plumage details with clarity.

To give a more complete, broader picture, following IOC taxonomy, there are six Dryocopus species: Black-bodied Woodpecker, Lineated Woodpecker, Pileated Woodpecker, White-bellied Woodpecker, Andaman Woodpecker and Black Woodpecker. There are 11 Campephilus species (all confined to the Americas), with the two largest presumed extinct: Powerful Woodpecker, Crimson-bellied Woodpecker, Red-necked Woodpecker, Robust Woodpecker, Crimson-crested Woodpecker, Pale-billed Woodpecker, Guayaquil Woodpecker, Cream-backed Woodpecker, Magellanic Woodpecker, Ivory-billed Woodpecker (presumed extinct) and Imperial Woodpecker (presumed extinct). Note that Helmeted Woodpecker has now been moved to the genus Celeus.

Two Vitally Important PFRA Community Pastures in Manitoba (and Saskatchewan)

The Ellice-Archie and Spy-Hill-Ellice PFRA community pastures are two grassland gems of critical importance to grassland birds in Manitoba. This post is a very brief introduction to their importance for grassland birds and why they are such a key piece for our efforts to retain a grassland ecosystem with a full suite of species (when so many grasslands are under threat of being converted).

The two PFRA community pastures straddle the Manitoba-Saskatchewan border near the town of St-Lazare in Manitoba and Spy Hill in Saskatchewan. As you can see from the Google earth screen shot below, the pastures are large enough that they can be seen from a zoomed out aerial view (this is vitally important for area-sensitive species and also because most of our grasslands are only tiny remnants). You can compare their size with some other visible features such as Riding Mountain to understand their importance. No other grassland in Manitoba is so large.

This detailed image gives you a better sense of the extent of the pastures (a red asterisk is placed near the centre of each pasture). You will also note the white rectangle in Saskatchewan near the pastures which is a large potash mine and another cause for concern in this area:

This zoomed-in image shows how the landscape is structured here. The Assiniboine and Qu'apelle Rivers meet here and both carve deep river valleys. The lower shelf of the river valleys has large and tall riparian deciduous woodlands (also known as gallery forests), the steep slopes have more scrubby oak and aspen vegetation and then, as you climb out of the valleys you are greeted with the vast open prairie on top. This is a glimpse into the way it used to be across the northern prairies before they were ploughed and divvied up. The photo below that also gives a sense of how the river valley climbs to the grasslands on top.

If you'd like to have that feeling of standing in a sea of grass, then this is your place! These three photos give you a sense of the magnitude of the grasslands here.

Unfortunately, some parts of the pastures have been seeded to non-native grasses but there are still large sections of native grasses with high abundance of grassland birds. Some of the key species are introduced below:

These pastures are a key site for the Chestnut-collared Longspur (Calcarius ornatus) in Manitoba. This species is highly threatened with red listings as follows:
International listing (IUCN): Near-threatened.
Canadian listing (SARA): Threatened.
Manitoba listing (ESEA): Endangered

In just two days, I counted over 200 Chestnut-collared Longspurs here this summer and that was in only a small section of the southern pasture. Here are three photos of a male, female and their nest with 6 eggs (click back). See also: http://birdatlas.mb.ca/speciesatrisk/species/ChestnutcollaredLongspur/species.htm

These pastures are also important for the Sprague's Pipit (Anthus spragueii) in Manitoba. This species is highly threatened with red listings as follows:
International listing (IUCN): Vulnerable
Canadian listing (SARA): Threatened.
Manitoba listing (ESEA): Threatened

In just two days, I counted over 70 Sprague's Pipits in one section of the pasture and the neighbouring Nature Conservancy of Canada holdings. The density of this species, which is sensitive to edge effects, is unparallelled anywhere else in Manitoba and that is presumably due to the extensive size of the grasslands.

2015 has been a very strange years for grassland bird distribution in Manitoba. Interestingly, we are finding many more Baird's Sparrows (Ammodramus bairdii) than usual and in sites further east and north of their recent occurrence in this province. Finding 4 Baird’s Sparrows in these pastures, where they have not been recorded since the 1980s, was very special for me. One of these birds was very close to Nature Conservancy of Canada holdings in this important grassland area. This species is listed as Special Concern federally in Canada but in considered Endangered provincially under Manitoba’s Endangered Species and Ecosystems Act.

The above three species are the key grassland specialist species in this pasture; however, other Species At Risk occur here too such as this Short-eared Owl (Special Concern) photographed quartering over the pasture.

Other Species At Risk such as Burrowing Owl, Ferruginous Hawk and Loggerhead Shrike have been recorded here in the past and could occur again in future if these pastures are safeguarded.  Some other important grassland birds that are not (yet) considered Species At Risk such as Grasshopper Sparrow (photo below) are also found here in good numbers.

Of course, many other birds make their home here: raptors include Red-tailed Hawk, Swainson's Hawk and Northern Harrier (photo below)

Upland-breeding shorebirds that breed in this pasture or close to it  include the Marbled Godwit (two photos below of these large shorebirds defending their territory)

 

The Upland Sandpiper also breeds here in good numbers:

... as does the Willet (seen here perched on a pasture fence post).

This is also one of the very best places in the whole province of Manitoba to see Mountain Bluebirds.   Eastern Bluebirds are very common in Manitoba but Mountain Bluebirds are becoming increasingly rare and difficult to see (perhaps due in part to Eastern Bluebirds expanding westward with the placement of bluebird boxes). In this part of the world, the Mountain Bluebird is a prairie species to watch! 

Exploring the river bottom forest and the shrubby hillside of course will produce a much more comprehensive list of species; however this area is most significant for threatened grassland birds. We are watching to  ensure these pastures remain as pastures and continue to convey the great benefits to the prairie ecosystem that they have for so long! For more information, see: http://www.gov.mb.ca/conservation/cdc/pdf/stlazare.pdf

Yucatán endemics

The Yucatán Peninsula is a flat limestone shelf that extends northward from Central America. This peninsula includes the three Mexican states of Yucatán, Quintana Roo and Campeche and northern Belize and northeastern Guatemala. The limestone rock formation means the soil layer is very thin and the topography is generally flat, unlike most of the rest of Mesoamerica. There are some small hills in parts of the peninsula and the Mayans use these to their advantage. In fact, they even contributed to the hilly topography of the area by seeking height in their architecture and building new pyramids atop the old. Here are two photos of the Mayan ruins as Uxmal (the letter “x” is pronounced like “sh” when used in a word of Mayan origin – though not necessarily so in recent writing conventions of the more than 20 Mayan languages that are spoken by more than 6 million people in this region today). As you can guess from the second photo, the Mayan ruins can make wonderful birding sites, especially where the forest has grown around the ruins and where there are tall fruiting trees, that maybe were once a food source for humans, that attract the birds. In some places, you can climb some of the pyramids and look straight into the canopy, giving a rare and privileged observation point of life in the tree tops.



The unique geology of the area has given rise to some different habitat types from those found elsewhere in the region and this has produced a certain amount of endemism. One of these unique habitats was in fact the very first image on my retina of the Yucatán Peninsula. As I flew southward towards Cancun, we crossed over a strip of very brown (dry) looking habitat between the coast and the greener interior, clearly visible from the plane (I always ask for a window seat!). You can see this area stands out on a google map – notice the browner strip I have marked with an ellipse.


This narrow strip is known as “coastal dune scrub”, sometimes also called “thorn forest” – although thorn forest is found in other coastal dry areas such as on the Pacific side. Despite the similarity of this habitat with thorn forests elsewhere, the geographic isolation of this dry forest from other dry forests means that quite a few of the plants are endemic. The dryness of this strip is related to precipitation levels and soil type, in particular a calcareous sand bar that differs from the limestone bedrock of most of the peninsula.

Of the bird that inhabit this dry strip, the most intriguing is the Yucatan Wren. Why, well because this species’ entire global range is confined to this narrow strip of habitat (a range map for this species matches the brown patch inside the ellipse on this map)! The Yucatan Wren is in the same genus as the Cactus Wren and almost as large and equally noisy. Their beautiful brown and white markings camouflage them nicely against the brown and white environment they live in as seen in these two photos!

The Mexican Sheartail, a small hummingbird, is another endemic of the coastal dune scrub with a very similar global range to the Yucatan Wren, mostly confined to this same coastal strip. I say mostly because there is a very small disjunct population of this species across the Gulf of Mexico in a dry area on the coast of Veracruz. In the Yucatán, the range of the Mexican Sheartail also extends slightly further east than that of Yucatan Wren.

The Zenaida Dove is not a Yucatán endemic because they occur on Caribbean islands as well as the Yucatán Peninsula. Nonetheless, where they do occur in the Yucatán is once again confined to the northern coastal strip, in particular areas with sand dunes, as shown here (first a bird feeding on the sand and then a pair perched up).

Most of the other Yucatan endemics are not as restricted as the sheartail and the wren and extend further south on the peninsula to varying degrees. One example is the Black-throated Bobwhite, also known as the Yucatan Bobwhite, whose range is most of the northern half of the Yucatán Peninsula but also has some smaller disjunct populations in Honduras, Guatemala and Belize. This species occurs in scrubby habitats that occur through the limestone shelf rather than the more forested areas. Here is a pair out crossing a road near Río de Lagartos (River of Lizards) in the coastal strip. The second shot shows their rather elegant pas-de-deux, up on tippy toes (and without the shoes!)

The Ocellated Turkey is also found throughout the peninsula; however they are extremely difficult to see anywhere, well, anywhere except Tikal in northeastern Guatemala, where they roam around at the base of the pyramids as if they own the place! The first photo show two birds while the second photo is zoomed in to show the remarkable iridescence of the feathers.

The Yucatan Jay is a Yucatán endemic that is found through most of the peninsula but is photographed here in the northern coastal area. The top bird in this photo is an adult (black bill), whereas as the bird with the yellow bill at the bottom is an immature bird. The brighter marking of the immature plumage, at least in terms of bill colour, is intriguing. It was also interesting to observe the immature bird apparently collecting nesting material. The Yucatan Jay and their close relatives (Bushy-crested Jay, Purplish-backed Jay and San Blas Jay) all have a cooperative breeding system with “helpers” assisting the parents in rearing the young. It seems likely therefore that the bill colour differences by age carry important social information about who has what role in the complex “extended family” arrangement.

The Gray-throated Chat is endemic to the region but extends slightly beyond the peninsula towards southeast Veracruz and into Guatemala. This species, however, is not found in the northern coastal scrub zone and is generally in slightly wetter but still scrubby (semi-arid to semi-humid) habitats. The first photo shows a male and then a female. This species and their sister species the Red-breasted Chat have attracted some interest of late as genetic studies have suggested that they may not be Wood-Warblers as previously thought… some have proposed they be in a family of their own!

The Yellow-lored Parrot, also know as Yucatan Parrot, is another endemic of the Yucatán Peninsula. Unfortunately, I only ever saw this species in flight…

The Yucatan Woodpecker (also known as Red-vented Woodpecker) is an endemic that occurs over most of the peninsula. Here is a different photo of this species from my previous post. The small size of this woodpecker means they can do well even in areas of the peninsula where the trees are quite small and in scrubby areas.

As I mentioned in the previous post, the yellow nasal tuft of the Yucatan Woodpecker is one of the features that separates that species from the dubius subspecies of Golden-fronted Woodpecker that occurs on the Yucatán Peninsula. Unlike, other subspecies of Golden-fronted Woodpecker, this race has no gold and a whole lot of red! Obviously the people who named this species were looking at a different subspecies at the time!

The Black Catbird is, well you guessed it, another endemic that occurs widely in scrubby habitat on the peninsula and islands off the coast. Behaviorally speaking, they are quite similar to Gray Catbird, though perhaps a little more skulking.

This next species is not an endemic but the stunningly beautiful Turquoise-browed Motmot has a fascinating disjunct distribution with a population in Central America extending from Costa Rica up to southwestern Chiapas and then a population over on the Yucatán Peninsula that is separated from the Central American birds by at least 400km. It is not clear if this disjunction is a result of these birds have recently disappeared from the intervening areas or whether it is older. Since they like forest edge a lot they seem quite at home in Mayan ruins and will use pyramids as nesting sites. Like some other motmots they will swing their tail from side to side in a jerky pendulum action, earning them the nickname “pájaro reloj” (clock bird). The magnificent tail with the exposed lower shaft and the broad "racquets" at the end is indeed pendulum like, but more colourful than any grandfather clock I have ever seen.

This next species is or isn’t an endemic depending on your taxonomy. The White-browed Wren is variously treated as a Yucatán endemic species, or a an endemic subspecies of Carolina Wren (can you see the plumage differences in this poor quality photo?).

Most of the Yucatán endemics, as you may have noted from the above descriptions are not true forest birds but rather birds of scrub habitat or at least more open forest types. Some however do not like the really dry parts of the peninsula and are therefore not found in the coastal dune strip of the northernmost and northwesternmost part of the Yucatán. The distribution map of these species is somewhat triangular in shape (following the parts of the peninsula with a little more rainfall and hence a little lusher vegetation) as shown in the map below:

One such species is the handsome Rose-throated Tanager. This is a male feeding in a fruit tree at the Mayan ruins of Cobá. This species is absent from the northwestern third of the peninsula.

The Green-backed Sparrow has a similar distribution to the Rose-throated Tanager, also being absent from the northwestern part of the peninsula; however, this species also extends further south and a little further west into the more humid forests of northern Guatemala and eastern Chiapas. This species is very similar in appearance to Olive Sparrow – if you know that species, see if you can spot the differences…

Some endemics of the Yucatán Peninsula actually have an even more eastern distribution in the sense that they are only found in the semi-humid scrub on the eastern side of the peninsula, which gets more precipitation than the thorn forest and do not spread westward in the southern part of the peninsula. A good example of this is the Yucatan Vireo, seen here using their large bill on an unsuspecting berry…

Of course there are a few more Yucatán endemics which I didn’t get satisfactory photos of , such as the Orange Oriole, but this should give you a good introduction of what makes the are unique in terms of its avifauna. I will try to post about some of the other birds of the region soon (sorry, getting very busy with the atlas).

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!