Saturday, October 30, 2010

Owls of Peru – Part 3: Humid forests

Photographing owls in the humid forest is of course much more difficult than in dry forests due the tall and dense vegetation, frequent rain and humidity in the air, and near complete canopy closure that makes it extremely dark and so much harder to see movement and silhouettes. Even though I saw more species of owls in the humid forests, I have fewer species to offer in this post.

One of the highlights of this trip was getting superb and repeat views of Cinnamon Screech-Owl at La Esperanza (as I mentioned in the previous post about Long-whiskered Owlet). The Cinnamon Screech-Owl is a rare and patchily distributed species that seems to be associated with outlying ridges more than with the eastern slope of the main Andean cordillera (unlike their counterpart the Rufescent Screech-Owl). Our first view of this species was the female photographed below (we thought for a second we had found the owlet) but despite being so difficult to see elsewhere, we had multiple sightings at La Esperanza – remarkable! In the next two photos see if you can see the differences between the female (first) and male (second)?


… the male has a deeper colouring overall and darker feathering of the facial disk and perhaps darker streaking as well (and a different voice). Can’t resist sharing a few more photos of this stunningly beautiful, little owl showing the underpart and upperpart colouration (look at the magnificent tail pattern and the barring in the flight feathers too!)…




At a similar elevation to Cinnamon Screech-Owl (slightly lower overall) one can find the much larger Band-bellied Owl. Actually, Band-bellied seems to co-occur with Rufescent Screech-Owl in many areas. I managed to see Band-bellied Owl twice on this trip, once near Moyobamba and again on the Manu Road, but in the tall cloud forest it proved extremely difficult to get photos of this beauty. The photo below was the best I managed. The four species in the genus Pulsatrix (Spectacled, Band-bellied, Short-browed, and Tawny-browed) are all very similar and all sport dark upperparts and breast contrasting with a pale belly and with prominent white or buff face markings that frame the face in “spectacles” of sorts…

The Ferruginous Pygmy-Owl occurs across a wide range of elevation in South America and, at least in my limited experience, seems much more nocturnal in habits than the bird that most North Americans call Ferruginous Pygmy-Owl (many now consider the Central and North American taxon to be a separate species called Ridgway’s Pygmy-Owl, although the AOU has not split them yet). These photos were taken in Moyobamba at the same elevation as the Band-bellied Owl. This bird had an interestesting habit of appearing more rufous from certain angles and more brown from other angles...

If you descend the eastern slope of the Andes towards the Amazon basin, you come into the range of the Tawny-bellied Screech-Owl complex. Some authors in fact, now split this species into two: Northern Tawny-bellied Screech-Owl (north of the Amazon) and Southern Tawny-bellied Screech-Owl (south of the Amazon). I was fortunate to get some great looks at Southern Tawny-bellied Screech-Owl on the lower section of the Manu Road near Atalaya. You can see how this species got their name.


I was particularly fortunate to watch this owl consume a cricket (though the views were a bit vertical). Just as I have watched Eastern Screech-Owls do, they seemed to remove certain hard parts first, for example the legs...

That ends this post on the owls of Peru. You can view larger files of these photos at: http://artusophotos.com/3_Nightbirds/index.htm (and other nightbirds of course!).

Saturday, October 23, 2010

Owls of Peru – Part 2: Arid Habitats

Western Peru experiences a formidable rain shadow, which creates a remarkable diversity in habitats. Simply put, all the moisture from the Amazon basin being pushed up the Andes (the prevailing winds are from southeast in this region) gets sucked out on the eastern side as moist air rises and condenses into rain (or snow). This leaves almost nothing for the west side, the leeward side, i.e. as air descends the western slope of the Andes there is no moisture left in it. Maybe your first image of Peru is of lush jungles, but if you are west of the Andes, it should be more like desert and arid scrub or tropical dry forest. So, you might not be expecting to see species like Burrowing Owl as my first Peruvian owl, but the smallish, pale desert subspecies nanodes is common here (much more common than this species is where I live in Manitoba, Canada)...

In the tropical dry forests along the coast (west of the Andes), one of the most common owl species is the diurnal Peruvian Pygmy-Owl. This species comes in a range of colour morphs – here a greyish bird, a brown bird and a rufous bird to show some of the range in colouration.


The Peruvian Pygmy-Owl like all of their congenitors in the genus Glaucidium is tiny (about 16cm though even this dwarfs the Long-whiskered owlet in my previous post which measures a mere 13cm). This photo of a Peruvian Pygmy-Owl being mobbed by an Amazilia Hummingbird should give you a sense of the size.


But don’t be fooled by their size – these little birds pack a lot of punch and can take prey much larger than they are. Can’t you see the feisty personality in their eyes?


As with so many owl species, females are larger than males (female is the lower bird in this pair). In this pair the female has a stronger rufous plumage colour wheras the male is browner but note that colour is not indicative of sex generally.


There are nocturnal owl species in the dry forests too. The Tumbes Screech-Owl (Megascops pacificus) occurs in dry coastal forests of northwestern Peru and southwestern Ecuador. Some authors consider this to be a subspecies of the Peruvian Screech-Owl (Megascops roboratus). This photo shows a grey morph bird (apparently the rufous morph is rare).


While out at night in Chaparrí, we heard a descending hoot call that struck me as being very similar to one of the alarm calls of Eastern Screech-Owl (a series of descending hoots is given and will escalate to “barks”, rattling calls and bill snapping if a threat persists). Sneaking up slowly, I spotted the owl perched about four feet off the ground and looking straight down. The bird was so intently focused on the ground and giving the alarm call persistently. This lead us to conclude that there must have been something like a snake in the leaf litter that was stressing the owl. We never did see a snake so this is only a guess but we got fantastic looks at the owl, who was so focused on the ground that they seemed oblivious to our presence. Here are a few examples of the photos I got…



Over near Jaén, we had much briefer looks at the Peruvian Screech-Owl, the interior species (or subspecies) that is found in dry intermontane river basins and hillsides, especially in the Marañon Valley. Not a great photo though but compare this bird, which is larger and has a proportionately longer tail, with the previous photos of Tumbes Screech-Owl. There are also differences in song…


The dry forest also extends to considerable elevation along the western slope of the Andes and the intermontane valleys. Up above 1800m ASL, the forests are much more “temperate” than tropical in appearance and this is the home to the very little known Koepcke’s Screech-Owl, discovered by great Neotropical ornithologist Maria Koepcke (she thought this taxa to be a race of Peruvian Screch-Owl) but not described until after her death and named in her honour. Koepcke’s Screech-Owl is very poorly known and very patchily and sparsely distributed, so seeing a pair of Koepcke’s Screech-Owls roosting by day was one of the highlights of this trip. The fact they were in, of all things, an introduced eucalyptus tree, only softened the high ever so slightly…


Since we spotted them in the late afternoon, we waited around for them to get active. They began allopreening (preening each other) and calling softly towards dusk.


These owls were high up in the eucalyptus and in amongst many cluttered twigs and branches. As it turns out my best opportunity to see them up close and personal came about an hour before dawn, when I found this bird out on the prowl. Notice, for example, the heavier markings on the breast and belly (also against a whiter base colouration) compared with Peruvian and Tumbes Screech-Owls. You will also notice the paler bare part colouration. Needless to say I was elated to get these photos of this secretive species.


In the dry Apurimac Valley (Abancay area) there is a currently undescribed taxon of screech-owl that has some consider conspecific with Koepcke’s Screech-Owl, but others favour treatement as a full species (awaiting further study). This taxon is nicknamed the Apurimac Screech-Owl and is paler in colouration and shows differences in voice. Another highlight for me was to see this bird after having seen Koepcke’s Screech-Owl (seeing an undescribed species/taxon is always a thrill even if you are not the one to discover them). So, let me introduce you to the Apurimac Screech-Owl…


Certainly a beautiful bird but is this a full species? Well, the song and calls I heard were similar in pattern to Koepcke's but did seem faster and of a higher frequency and there were some plumage differences (colder grey overall, lacking brown tones and also lacking the ochre/greenish tones in the tarsi and with greyer bare part colouration… though none of these mean very much in and of themselves). Since recently more and more authors are coming to accept that Tumbes and Peruvian Screech-Owls function as reproductively isolated species, it will be interesting to see what the conclusion on the Apurimac versus Koepcke’s Screech-Owls is in the long run. So, I end this post with this photo of a most handsome pair of Apurimac Screech-Owls – one of the mysteries of the Peruvian night!

Stay tuned for some owls of Peru’s humid forests…

Tuesday, October 19, 2010

Owls of Peru – Part 1: LONG-WHISKERED OWLET

I recently spent three amazing weeks in Peru. The biodiversity of this region is truly spectacular and I managed to see 562 species in three weeks (contact me for species list). Included in those 562 species were 16 owl taxa, including one of the least known species on the planet and an undescribed species. What could be better than that? Those who know me can vouch for my obsession with owls, but even for an obsessed, all-night owler, that is a fantastic total.

This trip started with an invite from, as it turns out, an equally owl-obsessed birding friend, Alan Van Norman. Alan had organized a trip to Peru with Birding Ecotours that was tailored to look for owls and he invited me to tag along. That offer was too good to refuse, so I joined Alan and Eduardo Omeche for 10 days of owl-searching in the north and then headed for 10 days of birding on my own in the south (a new expereince for me as I usually bird and backpack around on the cheap). I will blog more generally about this trip in the weeks to come but, as usual, let’s start with the nightlife of Peru…

A big part of the inspiration for this trip was the quest for the bird that is sometimes referred to as the holy grail of Neotropical birding – the Long-whiskered Owlet. Discovered in 1976 and only ever seen a handful of times in a tiny area of Peru, the call of this species remained unknown until a few years ago when one was caught in a mist net and placed in a tent, from where the bird started to sing and was recorded. That recording made it possible to search for this bird. So Alan and I dedicated one night at Abra Patricia and three nights at the La Esperanza, a community conservation project where the owlet was found very recently (http://www.neoprimate.org/), searching. Like so many others, at Abra Patricia we had no luck but La Esperanza, well, read on...

La Esperanza requires a long hike in on a steep and extremely muddy trail (it took us 6 – 7 hours to hike in and we had mules for the packs). There are two rustic cabins where you can stay. On our first night we had no luck with the owlet although we had great looks at Cinnamon Screech-Owl (photos below) and heard Rufous-banded Owl and White-throated Screech-Owl. The sighting of the Cinnamon Screech-Owl was interesting because it happened very shortly after Eduardo had played the owlet tape on spec and a pair flew in, possibly in response to the owlet tape. On the second night, we heard the Long-whiskered Owlet call around 8pm. What followed was a long effort to bring the bird in, which seemed to be working. The call got closer and closer and we waited with baited breath. Then, that moment that makes your heart beat fast – two owls flew in! As we got the flashlight on an owl, the two teenagers who were our guides from the community conservation project got excited, telling us we were looking at the owlet. Unfortunately though, Eduardo, Alan and I were all doubtful – something was wrong! When the owl flew away and we discussed the features and looked at photos Alan had taken it became apparent that we had been looking at a Cinnamon Screech-Owl. The fact the we had had two occasions when Cinnamon Screech-Owl respond aggressively to the owlet tape and the fact that the guide had misidentified the bird had us very concerned – maybe some of the reported sightings from La Esperanza were in fact NOT the enigmatic owlet after all. At least we knew that some of the sightings were of the owlet as we had seen the photos but we suspected that this bird is nowhere near as common at the site as our young guide would have had us believe. Since we were there in August (dry season) and all of the precious few sightings of Long-whiskered Owlet we were aware of were between December and May (wet season) there might also be seasonal differences in calling and response rate that were working against us.

With that major let down, everyone slid back down the mountainside to get some rest... well, everyone except me that is – I stayed up all night in a vain effort to find the owlet but didn’t hear so much as a peep. Nightfall on our third and final night in La Esperanza found us in position on a steep slope where we had heard the owlet call the night before. We weren’t waiting long when the rain began (as so often happens when you go out at night in cloud forest). We waited and waited until 10pm or thereabouts when the rain started to let up and then tried searching for the owlet in vain for an hour or so. In the continuing drizzle and processing all that had happened, Alan and Eduardo decided to abandon the search and get some rest. I, on the other hand, was too stubborn to give up… after all, how many times in your life do you get a chance to search for Long-whiskered Owlet?

So, I walked up and down on the steep, narrow, muddy trails, pausing to listen at promising spots - nothing, nothing, nothing! By around 4am the drizzle had stopped and sky was much clearer and a calling Lyre-tailed Nightjar gave hope that the night might come alive. Closer to 4:30, it happened – a moment i won’t soon forget – I heard a Long-whiskered Owlet call from a ridge above me. A few seconds to calm my beating heart and I whipped up the trail as quickly and quietly as I could and up a narrow side trail to get closer to where I had estimated the sounds came from. I paused on the mountainside; a few minutes of intense silence, then, yes, there was the call again and much closer this time. Dawn was approaching and I had to think fast. I worked the trail trying to assess options. Since the owlet was calling from up on the ridge, I concluded my best chance was to find a spot with an opening where I could see uphill. In the dense cloud forest that was no easy task, but there was one spot where I felt I might have a chance. The problem was my spot was on a very steep slope and rather precarious. Calming my emotions, I started a dialogue with the enigma… and the owlet called back! What followed was an agonizing 45 minutes with the owlet calling ever closer to where I was standing.

As always, when searching for owls, your eyes and ears are on “high alert”. After so much staring into the darkness, I caught the silhouette of movement – something small had flown in and landed above my head!! Shining my flashlight, I saw the bird almost immediately - an absolutely diminutive owl! And, as I watched, this tiny little owl pointed their head skyward and called… there was no doubt about it – I was looking at a LONG-WHISKERED OWLET!! I was in ecstasy as I watched the owlet simultaneously raise their head and lower their wings to call, the long whiskers visible with this action. A once-in-a-lifetime moment to see such a secretive bird that has been seen by so very few!

I then tried to take some photos but because the owlet was right above me and I was standing on a steep slope, I was having enormous difficulty holding the light and focusing the camera simultaneously. I certainly wish my companions had been there at that moment! I took a couple of very out-of-focus photos before deciding that the only way was to try to put the light on the ground pointing up. Ordinarily, that might have worked but on this occasion I nearly fell off the mountainside trying - no chance! Of course, with dawn approaching the owlet did not stay there much longer and all I could do was watch it fly off into the night without a good photo to show for it. My souvenir, for what it is worth, is this horribly out of focus photo but I still won’t forget the thrill of finding this mysterious creature! (hey, but it wasn’t an Ivory-billed Woodpecker)…


Well, that photo is not much to look at though at least you can make out the owlet. Even though I missed the photo, this remains one of the best birding moments of my life.

Anyway, I will soon post part 2 of the Owls of Peru but this story could wait no longer. And I promise the next post will have lots of pretty pictures!
 
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