 It
was a steamy day in the Philippine lowlands of eastern Mindanao. It had
rained heavily during our two-hour jeep ride to the remnant forest, and
then we'd been walking for hours, taking cover with each passing rain-shower.
By late morning our little group was strung out along a half-abandoned
logging road, trudging uphill for some time, and then down into a little
swale. I was alone between segments of our party at the time, but suddenly
I 'felt' like something was watching me to the left. Or perhaps I had seen
something fly up to a perch in the woods to my left out of my peripheral
vision. I stopped, turned, and was confronted by this amazing bird (left):
a male Mindanao Wattled Broadbill, This was one of my 'most wanted'
endemics from the Philippines and the joy of finding it — or of it finding
me — was quite wonderful.... And then to get photos!. Next to the Great
Philippine Eagle, I consider the two species of Wattled Broadbill in the
Philippines to be the most special birds of that magical archipelago, and
the highlight of any trip.
Broadbills are among the most spectacular birds on earth but most are
exceptionally difficult to observe. This combination makes them perhaps
my favorite or all families of birds.
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 Or
I should say: my two favorite families of birds! Because the recent DNA
evidence (Moyle et al. 2006) shows that two lineages of broadbills diverged
about 55 million years ago and have been on separate evolutionary paths
ever since. One lineage evolved into the green broadbills of Asia (Calyptomena)
and the lowland broadbills of Africa (Smithornis; together they
now form the Calyptomenidae),
while the other lineage had further branches. First a New World species,
the Sapayoa, split off about 52 million years ago, then the Asities of
Madagascar perhaps 46 million years ago (Prum 1993 had shown that Asities
were 'nested' within the old-school broadbill assemblage), leaving a set
of mostly Asian broadbills (including the Mindanao Wattled Broadbill;
a female is shown to the right) and Grauer's Broadbill in Africa (more
on that below).
It is remarkable that both lineages of broadbills — which I treat as two families here — both have Asian and African components. However, in both cases, most of the species are Asian. I recall being overcome with wonder while looking through a drawer full of specimens for Borneo residing at the Western Foundation of Vertebrate Zoology. They were "salvage" specimens — that is, they were collected by ornithologists in lowland forest slated to be clearcut in the near future under the horrendous logging practices of Malaysia and Indonesia. Rather than losing the birds along with their habitat, they were "salvaged" to provide important scientific specimens. The Banded Broadbill Eurylaimus javanicus wore a subtle mix of gray, yellow and pinkish-red, while the Black-and-red Broadbill (below) was a gorgeous clash of crimson and black. These two species also had particularly impressive broad bills, as is nicely shown in the sequence below: video captures of Black-and-red Broadbill in Borneo by Rita Carratello. |
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 Eurylaimid
Broadbills live in the subcanopy of the Old World tropics: 8 species in
southeast Asia, the Philippines, and Borneo & Sumatra, plus the one
in central Africa. Most are lowland birds although some are highland species,
such as Long-tailed Broadbill Psarisomus dalhousiae of s.e. Asia
and the Greater Sundas.
Asian broadbills are generally located by their calls. That of Black-and-yellow Broadbill (right) is a very unusual, accelerating cacophony that proves to be a characteristic sound of the Bornean lowland forest. Once learned, this species proves to be quite common. But it usually remains difficult to actually see its lovely mix of pink, yellow, and black patterns. In Danum Valley, Borneo, both Banded and Black-and-yellow Broadbills proved to be much less rare than supposed once their calls were learned. All are responsive to tape playback but may still prove frustrating difficult to locate in the leafy forest above. Eurylaimid Broadbills eat primarily flying insects that they catch from
their subcanopy perches, although they will also take a variety of fruits
(some species are more fruit-eating than others). They build elaborate,
hanging, purse-shaped nests. Black-and-red Broadbill drape their nests
over quiet forest backwaters and streams, and can often be found around
the water's edge. The nests of the Eurylaimid Broadbills — and of Asities
and Sapayoa — are globular masses suspended 10-30 cm below a branch, and
the entrance is on the side of the nest. In this respect they differ from
the Calyptomenid Broadbills whose nest is suspended closer to the branch,
and the entrance of which is at the top of the mass (Prum 1993, Moyle et
al. 2006).
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 Grauer's
(or African Green) Broadbill is the only Eurylaimid Broadbill in Africa
(left in a wonderful photo by David Fisher of an adult at its nest).
It is endemic to the Albertine Rift at the intersection of Congo, Uganda,
and Rwanda. It is amongst the most sought after birds in Africa. It has
recently been found regularly in Mbwindi Swamp in Bwindi-Impenetrible Forest
park in s.w. Uganda. David Fisher's photo is from that locale; researchers
took his group to two nests in July 2006 [and David's photo is actually
a combination of two shots — the nest and the bird carrying food]. Unfortunately,
I missed it on my own day visit there several years earlier, despite having
a local expert guide. My guide had found a nesting pair just a couple months
before but the young had just fledged and the birds dispersed. It does
not have the broad bill of other species but looks rather like a tiny green
puffbird sitting quietly in the forest canopy. Unlike other broadbills,
graueri
has a thin, soft, high-pitched note.
Grauer's Broadbill diverged from the Asian broadbills in this group about 35-45 million years ago, but is more closely related to them than anything else (Moyle et al. 2006). Asities and Sapayoa are more ancient lineages along this same evolutionary branch. Thus its lineage is less ancient than the Calayptomenid Broadbills, Asities, or the Sapayoa. However, one way of categorizing the evidence is to further separate out this wonderful little bird as a monotypic family, leaving only the remaining Asian genera in the Eurylaimidae. Another way of categorizing the evidence is to consider all the broadbills to be just one family, but in that approach one must lump the Asities and the Sapayoa with them. I prefer the approach that highlights the diversity of this group and the long evolutionary lines of each clade, but some taxonomists prefer to emphasize relationships and thus lump all of them together. In the latter case, Sapayoa would be a remnant broadbill in the New World. Time will tell which approach gains wide acceptance. For the moment,
I treat this assemblage in a similar manner to the SACC approach to the
barbet/toucan evidence, and emphasis diversity by maintaining four families:
Eurylaimid Broadbills, Calyptomenid Broadbills, Asities, and Sapayoa.
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| Photos: The Mindanao Wattled Broadbill
Sarcophanops steerii was in the PICOP forest of Mindanao on 27 Dec
2005. The Black-and-red Broadbill Cymbirhynchus
macrorhynchus was video taped by Rita Carratello at Borneo Rainforest
Lodge, Danum Valley, Sabah, Malaysian Borneo, in August 2003, and
then she provided these video captures from the tape. The
Black-and-yellow
Broadbill Eurylaimus ochromalus was taken along the access
road to Gomantong Cave, Sabah, Malaysian Borneo, on 31 July 2003. The Grauer's
(African Green) Broadbill Pseudocalyptomena graueri
as photographed by David Fisher in Bwindi-Inpenetrable Forest National
Park, Uganda, in July 2006. All photos © Don Roberson,
except those attributed to David Fisher and Rita Carratello, who hold those
copyrights, used with permission. All rights reserved.
Bibliographic essay Family Book: In the standard format of recent books in the Pica Press series, color plates are found separately (with facing page captions) from the text, giving the feeling this is meant to be a field guide. The quality of the paintings is good, at least to my eye, given my minimal experience in the wild with these great birds but more experience in handling museum specimens. However, not even well-printed plates can capture the glistening colors of these wonderful birds, and the "field guide" poses are stiff and lifeless. The introductory text appears up-to-date, and the species accounts seemed well-researched. I found no obvious errors in the maps or text, but then I know comparatively little about these families. Despite giving the book high marks for apparent accuracy and attractive paintings within the limits of the genre, how I wish for a more "old-fashioned" book on these special families, with full-page spreads of each species in habitat and evocative detail of each species' discovery to science! The "field guide" approach to the art, and the plodding quality of the scientific text, just does not do justice to these marvelous creatures. Yet for what it is, the book is generally well-done and a welcome addition to the bookshelf.The Handbook of the World volume covering this family (Bruce 2003) was, as expected, spectacular. But they also did not anticipate the findings about the true relationships in this group. Other literature cited: Bruce, M. 2003. Family Eurylaimidae (Broadbills) in del Hoyo, J., A. Elliott, & D.A. Christie, eds., Handbook of the Birds of the World, Vol. 8, pp. 54-93. Lynx Edicions, Barcelona.TOP |
