30 September - 5 October 1999

by Niels Poul Dreyer

I went to Bilsa Biological Reserve at the end of September 1999.  The 3000 hectares large reserve is found in the Mache-Chindul mountains 20 km from the Pacific in the province of Esmeraldas. Although Bilsa is located between the Tumbesian and the Choco Endemic Birding Areas, its habitat consists mainly of Choco forest.  It is one of the last stands of the Choco forests in Ecuador, as more than 97% of this important forest have been removed by logging companies and farmers.  The area was saved just in time from logging by the conservation organization Fundación Jatun Sacha.  About twenty percent of the reserve had been damaged and cut down but the foundation is working on replanting this part with seeds from several endemic rainforest trees.

The altitude of Bilsa is between 300-700 meters and the forest looks more like a cloud forest engulfed in mist than a true lowland rainforest.  According to the Birdlife International, the Choco Endemic Birding Area (Choco EBA) is one of the world's richest lowland biota with exceptional richness and endemism in a wide range of taxa including plants, reptiles, amphibians and butterflies.  (Dinerstein et al 1975 in Stattersfield A.J.  et al 1998).  Over 50 species are endemic to the Choco region which 44 occur in Ecuador.  A total of 16 the restricted-range species are presently thought to be threatened with a further 14 Near Threatened.  (Stattersfield A.J.  et al.  et a.l 1998).

A field team lead by K.S. Berg recorded 289 species over a period of 6 months between February and October 1998, spending approximately 1600 man hours along about 12 km of forest trails and in adjacent areas.  Some of the most interesting birds found on this survey were Plumbeous Forest-Falcon, Stump-tailed Antbird, Banded Ground Cuckoo, Lita Woodpecker, Lanceolated Monklet, Long-wattled Umbrellabird, Brown-bellied Scythebill, Orange-crested Flycatcher and White-throated (Dagua) Thrush Turdus assimilis daguae.  The latter was classified as a race according to Ridgley and Tudor 1989, but is now split to a separate species daguae, as it is has a different vocalisation, look and behaviour from its Central American counterpart.  (Berg, K.S.  1998).  Of the above mentioned species, I saw only Lita Woodpecker, the umbrellabird and the thrush during my stay.  Although I spent a long time watching a big antswarm, the ground-cuckoo proved to be too elusive.

The lower part of this EBA is poorly protected, particularly in Ecuador, so consequently Bilsa represents the last hope for such rare birds such as the Long-wattled Umbrellabird and the Banded Ground Cuckoo.  The reserve supports 5 threatened and 4 near-threatened species.

Access

I went to the Fundación Jatun Sacha office in Quito and booked my stay at the “Estación Biológica Bilsa”, paying 100 dollars for my 5 night stay.  As I was told that the road to the station was very muddy, I decided to hire a horse in order to make the trip easier.  I paid about 25 dollars extra for this.  I took a Ejectivos Esmeraldas bus from Quito to Quinindé which took 4 hours and thereafter stayed in a reasonable place called Hotel Sanz with a nice pizza restaurant.  However, breakfast was not available the next morning.  As malaria is widespread in Quinindé, I had to put up my mosquito net while sleeping in this hot town.

The next morning, I asked where I could take a truck by the name Rodo to "A la y de la Lagouna" which is about 35 km from Quinindé.  The truck could only bring me the first 30 km the way, and I had to walk about 2 hours, because the road was in very bad condition.  Fortunately, at the "A la y de la Lagouna" the horses were waiting for me, as the rest of the way was extremely muddy and heavy going.  The trip took all day, and I was extremely exhausted when I arrived to the station.

I was a bit shocked to see an armed warden standing at the gate to the reserve.  The station was locked up during the nighttime, and the guards were waiting outside, perhaps awake.  The reserve has been attacked by bandits possibly hired by a logging company and a couple of women raped and everything valuable stolen.  Conservation in this part of the world is a risky business, as the logging folks do not like having conservationists telling the locals that the mahogany timber sold by them for 20 dollars would fetch 20,000 in Europe and America.  The logging company which previously had felled 30,000 hectares in the area would not accept they were not entitled to destroy the remaining 10% of the forest.  Obviously they hoped to scare away the greens so they could harvest the last remaining patch.  It apparently did not work out that way, and consequently they moved farther to the north, where the timber interest now are in the process of harvesting primary forest trees with less opposition.

The station was a bit rustic, and it was not easy to get to a toilet at night as everything was locked up and I had to find the guards before getting outside.  The accommodation itself was okay, as I had my own room with a bed and mosquito net.

Birding

The birding was somewhat affected by the moist foggy conditions which prevail in the so called dry season from September to December.  It was very muddy on the trails, particular in the secondary growth areas.  Fortunately the folks were able to lend me some rubber boots, as I did not bring any.  In the primary forest and along the creeks the conditions were better.  I stayed away from the road, as it was nearly impossible to move around without carrying 10 kilograms of mud under my boots.

The fog made it hard for me to see the parrots, and I got only satisfactory views of Rose-faced Parrot, Mealy Parrots and Dusky-winged which were feeding in some fruit close up.  I could hear a few other parrot species such as parrotlets in the mist, but never got enough light to be able to identify them.  Only one day the fog cleared enough to get a view of a Black-tipped Cotinga sitting in the top of a distant tree.

On the other hand the forest was very lively and the hummingbirds were very active especially in the heliconias.  The most conspicuous were the White-whiskered Hermit and a few Green-crowned Brilliants.  Down in the banana growth near the riverbed the strange White-tipped Sicklebills were sucking nectar from curve formed flowers from the heliconias.  On the trails in the forest the Green-crowned Woodnymph were dominant, but a few Purple-crowned Fairy were around higher up in the trees.  At the edge along the river in primary forest at the end of the long trail the Barbthroat and Baron's Hermits were busy feeding in several types of flower, but the real prize were the sighting of the Tooth-billed Hummingbird.  It was sitting on a small vertical branch singing persistently and always returned after each venturing out.  According to Berg 1998, the expedition got the first tape recording of this bird, but I must have obtained the second, as it was very actively singing and preening.

Just next to the hummingbird lek I saw 6 umbrellabirds flying into a fruiting tree.  It took a while to get a view of the long wattle, but is a truly amazing bird.  I still wonder why it is necessary to carry around with a 25 cm long wattle!  During my stay I got terrific views of one sitting in a cecropia and feeding in a palm inside the forest.  In the morning we heard a persistent long drawn booming sound through the misty forest just like a warning horn from ships moving though fog.  I have been told that the umbrellabirds tend to approach more open areas during the rainy season when the palms fruit.  Bilsa is the last stronghold for this species in Ecuador and almost everybody visiting the place sees one.  Alternatively, it is possible to encounter the Long-wattled Umbrellabird along the Lita Road to Lorento.  However, it is rarer there as hunters shoot the birds, and I did not see any along that road.

Bilsa appeared to be the place to watch professional ant-following antbirds and woodcreepers.  At the botanical gardens there was a huge antswarm.  About 15 Plain-brown Woodcreepers were present at all levels and even two rare Northern Barred Woodcreepers approached the area as it gave some snarling calls.  At the front of the antswarm 2 pairs of Chestnut-backed, 2 pairs of Immaculate, +20 Bicolored Antbirds, 2 Ocellated Antbirds, 1 Tawny-faced Gnatwren were busy feeding on insects disturbed by the antswarm.  The next day I observed the same antswarm 100 meters farther downhill.  After having spent several hours watching this spectacle, I did not encounter any Banded Ground-Cuckoos, but people working at the station have in the past seen ground-cuckoos running across the road.

I played a tape of the Scaled Antpitta near the antswarm, but no bird came into view.  I expect it would better to try for it during the so called "wet season".  On the other hand, I was rewarded with a sighting of the rare Broad-billed Sapayoa (Manakin) sitting quietly in midstorey level, and in a mixed species flock it was possible to watch the special dark race of White-throated Thrush feeding in a tree together with some tanagers.  In the cecropias I got a good view of a Lita Woodpecker which looked more like a Yellow-throated Woodpecker than a White-throated.  It had a large yellow cheeks and a crimson crown.  Of non bird sightings were orange Harlequin Poison Dartfrog (Dendrobrites histrionicus), several interesting lizards seen along the riverbed and a group of five Mantled Howler Monkey (Alouatta palliata).  Other people at the station saw a Collared Anteater (Tamandua tetradactyla) while I was birding.

Birdlist

Cattle Egret Bubulcus ibis
common in open areas

Black Vulture  Coragyps atratus
common

Roadside Hawk  Buteo magnirostris
5 seen on the way into Bilsa Biological Station

Barred Forest-Falcon  Micrastur ruficollis
1 in secondary growth near the station

Spotted Sandpiper  Tringa macularia
1 at the river

Ruddy Pigeon Columba subvinacea
2 in the forest

Pacific Parrotlet Forpus coelestis
A flock seen on the way into the station

Rose-faced Parrot Pionopsitta pulchra
1 seen near the station

Bronze-winged Parrot  Pionus chalcopterus
+20 at the station

Mealy Parrot Amazona farinosa
+10 flying over and heared every day

Squirrel Cuckoo Piaya cayana
3  seen in forest

Tooth-billed Hummingbird Androdon aequatorialis
1 bird singing at a lek about 250 meters before the end of the southbound (main) trail

Band-tailed Barbthroat  Threnetes ruckeri
4 seen in the bushes along the river

White-whiskered Hermit  Phaethornis yaruqui
Very common in heliconias behind the station

Western long-tailed Hermit (Baron's) Hermit Phaethornis longirostris baroni
2 seen near the river behind botanical gardens

White-tipped Sicklebill Eutoxeres aquila
4 in heliconias along the river east of the station (Downstream from the washing place)

Green-crowned Woodnymph Thalurania fannyi
10 in the primary forest

Green-crowned Brilliant Heliodoxa jacula
+6 in secondary growth, very tame when perched.

Purple-crowned Fairy  Heliothryx barroti
4 in the primary forest

White-tailed Trogon Trogon viridis
3 in forest

Collared Trogon Trogon collaris
1 in primary forest

Black-throated Trogon Trogon rufus
5 seen in primary forest

Green Kingfisher Chloroceryle americas
1 flying along the river

White-whiskered Puffbird Malacoptila panamensis
2 not far from the station

Red-headed Barbet Eubucco bourcierii
1 in mixed species flock in the secondary growth

Pale-mandibled Aracari Pteroglossus erythropygius
15 feeding in cecropias

Choco Toucan Ramphastos brevis
+25 or more, heard all the time and seen often

Lita Woodpecker Piculus litae
1 on the edge between secondary and primary forest near the station

Lineated Woodpecker Dryocopus lineatus
1 on the way in

Red-rumped Woodpecker Veniliornis kirkii
1 in primary forest

Guayaquil Woodpecker Campephilus gayaquilensis
2 near the heliconias

Plain-brown Woodcreeper Dendrocincla fuliginosa
+15 in an antswarm flock

Olivaceous Woodcreeper Sittasomus griseicapillus
2 in the forest

Wedge-billed Woodcreeper Glyphorynchus spirurus
+5 in flock with other birds and some alone

Northern Barred-Woodcreeper Dendrocolaptes sanctithomae
2 in the antswarm flock, tend to be more retiring and hunt from higher levels

Black-striped Woodcreeper Xiphorhynchus lachrymosus
1 alone in the forest

Spotted Woodcreeper Xiphorhynchus erythropygius
+5 rather common

Streak-headed Woodcreeper Lepidocolaptes souleyetii
1 seen in mixed species flock in secondary growth

Red-faced Spinetail Cranioleuca erythrops
2 in the undergrowth

Spotted Barbtail Premnoplex brunnescens
1 in a mixed species flock

Buff-fronted Foliage-gleaner Philydor rufus
1 in a mixed species flock

Tawny-throated Leaftosser Sclerurus mexicanus
1 near botanical gardens

Western Slaty-Antshrike Thamnophilus atrinucha
4 stationary (2 pairs) in secondary mixed scrub and banana grows near the station

Streaked Antwren Myrmotherula surinamensis
2 in a mixed species flock

Checker-throated Antwren Myrmotherula fulviventris
6 seen

White-flanked Antwren Myrmotherula axillaris
8 especially in secondary growth

Slaty Antwren Myrmotherula schisticolor
4 in the primary forest

Chestnut-backed Antbird Myrmeciza exsul
1 pair at the antswarm, 2 pairs in the primary forest

Esmeraldas Antbird Myrmeciza nigricauda
1 pair near the river in primary forest

Immaculate Antbird Myrmeciza immaculata
2 pairs attending the antswarm

Black-headed Antthrush Formicarius nigricapillus
2 seen well crossing the trail, responsive to tape playback, they are not that shy!

Bicolored Antbird Gymnopithys bicolor
+20 attending the antswarm

Ocellated Antbird Phaenostictus mcleannani
2 attending the antswarm, tended to be at the centre of the action and on the ground, they were at first a bit retiring, but they are the leaders of the feeding frenzy.

Golden-faced Tyrannulet Zimmerius chrysops
2 inside the forest at midstorey level

Brown-capped Tyrannulet Ornithion brunneicapillum
2 seen well in a mixed species flock inside the forest

Yellow-bellied Elaenia Elaenia flavogaster
One near the station

Slaty-capped Flycatcher Leptopogon superciliaris
2 seen in a flock

Black-capped Pygmy-Tyrant Myiornis atricapillus
2 seen in a 6 meters tall tree in secondary growth with heliconias not far from the station

Scale-crested Pygmy-Tyrant Lophotriccus pileatus
Common  in secondary forest with heliconias

Common Tody-Flycatcher Todirostrum cinereum
1 in a mixed species flock

Pacific Flatbill Rhynchocyclus pacificus
1 inside primary forest, attracted to its call

Yellow-olive Flycatcher Tolmomyias sulphurescens
2 near botanical gardens

White-throated Spadebill Platyrinchus mystaceus
1 pair ? in secondary edge to primary forest, a retiring species

Ornate Flycatcher Myiotriccus ornatus
Very common, prefers treefall areas inside primary forest, perched about 10 meters above the ground

Black-tailed Flycatcher Myiobius atricaudus
2 in dark forest at midstorey level

Smoke-colored Pewee Contopus fumigatus
2 near the station

Dusky-capped Flycatcher Myiarchus tuberculifer
4 or more, perhaps common

Boat-billed Flycatcher Megarhynchus pitangua
1 near the station

Social Flycatcher Myiozetetes similis
4 in the open areas around the station

Snowy-throated Kingbird Tyrannus niveigularis
1 on the way in

Tropical Kingbird Tyrannus melancholicus
common on the way in

Cinnamon Becard Pachyramphus cinnamomeus
4 (2 pairs) in mixed species flocks

One-colored Becard Pachyramphus homochrous
Seen in dark forest higher up in the trees.

Broad-billed Sapayoa Sapayoa aenigma
1 seen near the botanical gardens

Red-capped Manakin Pipra mentalis
1 seen inside the forest

Black-tipped Cotinga Carpodectes hopkei
1 in a high canopy tree growing in the gully. Active hunting insects

Purple-throated Fruitcrow Querula purpurata
A flock of 10+ birds eating palm fruit

Long-wattled Umbrellabird Cephalopterus penduliger
A flock of 5-6 birds flew into a tree not far from the river, 1 seen well near the botanical gardens, heard its booming call every morning, a female seen near the station the first day

Gray-breasted Martin Progne chalybea
A few flying around the station, seen when it is not foggy

Southern Rough-winged Swallow Stelgidopteryx ruficollis
4 on more open areas next to the station

Band-backed Wren Campylorhynchus zonatus
2 next to the station

Bay Wren Thryothorus nigricapillus
Very common

Southern House Wren Troglodytes musculus
2 next to the station

White-breasted Wood-Wren Henicorhina leucosticta
2 pairs in the forest

Southern Nightingale-Wren Microcerculus marginatus
1 on the ground in primary forest

Song Wren Cyporhinus phaeocephalus
1 in low understorey in primary forest

White-throated Thrush Turdus assimilis
One thrush, a dark version of this White throated Thrush (Dugua) seen in a mixed species flock in a large tree on the opposite side of the road from the station

Tawny-faced Gnatwren Microbates cinereiventris
2 attending the antswarm near the botanical gardens

Variable Seedeater Sporophila corvina
several around the station

Dull-colored Grassquit Tiaris obscura
common along the roadside

Orange-billed Sparrow Arremon aurantiirostris
2 inside the forest

Buff-throated Saltator Saltator maximus
4 seen in secondary forest

Yellow-throated Bush-Tanager Chlorospingus flavigularis
Common in both secondary and primary forest

Dusky-faced Tanager Mitrospingus cassinii
Fairly common in primary forest, like vine tangles and thick foliage

White-shouldered Tanager Tachyphonus luctuosus
1 in the secondary forest

Blue-gray Tanager Thraupis episcopus
common around the station

Palm Tanager Thraupis palmarum
common in secondary growth

Orange-crowned Euphonia Euphonia saturata
2 in primary forest

Orange-bellied Euphonia Euphonia xanthogaster
6 or more, quite common in mixed species flocks

Emerald Tanager Tangara florida
1 in primary forest in a berry tree

Silver-throated Tanager Tangara icterocephala
Very common especially in secondary growth

Bay-headed Tanager Tangara gyrola
+50 or more, very common

Blue-necked Tanager Tangara cyanicollis
+10 in mixed species flocks

Green Honeycreeper Chlorophanes spiza
+5 common around the station

Purple Honeycreeper Cyanerpes caeruleus
2 in a flowering tree

Olive-crowned Yellowthroat Geothlypis semiflava
1 near the station

Choco Warbler Basileuterus chlorophrys
2 in secondary growth

Buff-rumped Warbler Basileuterus fulvicauda
8 along the river beds and near small waterfalls entering the river

Bananaquit Coereba flaveola
+15 or more, common in mixed species flocks

Lesser Greenlet Hylophilus decurtatus
4 in secondary growth

Chestnut-headed Oropendola Psarocolius wagleri
A flock of perhaps 15 birds were feeding on palm fruit not far from the station

Yellow-rumped Cacique Cacicus cela
A few around especially in secondary growth and in the canopy down in the gully

Scarlet-rumped Cacique Cacicus microrhyncus
4 inside the forest in middle to lower story in thick undergrowth

References:

Berg, K.S. 1999. A field survey of avian diversity at the Bilsa Biological Station Province of Esmeraldas, Ecuador. Fundación Jatun Sacha & Endowment for World Parks, Quito.

Fundación Jatun Sacha. Bilsa Biological Station Eugenio De Satillan N34-248. Quito. Telephone in Quito 432246. E-Mail

Hilty S. L., Brown W.L., Tudor, G. 1986. A Guide to the Birds of Columbia. Princeton University Press, New Jersey.

Dinerstein, E.,  Olson, D. M. , Graham, D.J., Webster, A., Primm., L., Bookbinder, M.P., Ledec, G. , 1995. A conservation assessment of the terrestrial ecoregions of Latin America and the Caribbean. World Bank, Washington DC.

Stattersfield A. J., Crosby M.J., Long, A.J. Wedge, D.C. 1998. Endemic Bird Areas, Priorities for Biodiversity Conservation. Birdlife International, Cambridge UK.
 

Please contact

Niels Poul Dreyer

DREYERN@wanadoo.fr
dreyernp@mail.tele.dk