Table Of Content© Biologiezentrum Linz/Austria; download unter www.biologiezentrum.at
Birds of La Gamba –
a call for research and scientific collaboration
Aves de La Gamba –
un llamado para la investigación y colaboración científica
Gerhard AUBRECHT & Christian H. SCHULZE
Abstract:TheknowledgeoftheavifaunaoftheLaGambaregion,CostaRicaisstilllimitedandcloselyconnectedwiththefoun-
dationoftheTropicalStationLaGamba.Specialattentionisdrawntothebiogeographicalsituation,birdconservation,endem-
icbirds,thefaunisticinventoryandecologicalstudies.Existinggapsinourknowledgeandpossiblecontributionsbyongoingre-
searchtoquantifyingtheimportanceofcountrysidehabitatstoactascorridorformovementsofforestbirdsareaddressed.
Keywords:avifauna,ornithology,TropicalStationLaGamba,CostaRica,ornithologicalresearch.
Resumen:ElconocimientoacercadelaavifaunadelaregióndeLaGamba,CostaRicaestáaunlimitadaoyestrechamenteco-
nectadconlafundacióndelaestaciónTropicalLaGamba.Especialatenciónesdadaalasituaciónbioegeográfica,conservación
deaves,avesendémicas,elinventariofaunísticoyestudiosecológicos.Seabordanlosclarosexistentesennuestroconocimiento
ylasposiblescontribucionesdelasinvestigacionesencurso,almomentodecuantificarlaimportanciadeloshábitatruralespara
actuarcomocorredoresdelmovimientodelasavesdelbosque.
Palabrasclave:avifauna,ornitología,EstaciónTropicalLaGamba,CostaRica,investigacionesornitológicas.
AcloselookontheavifaunaofLaGambareveals The area of La Gamba and the adjacent Golfo
theincreaseofknowledgeduringthelast10to15years Dulceregionwasneglectedbyornithologistsforalong
aswellasthegapsthatstillexist.Thethreecontribu- timeduringtheexplorationoftheCostaRicanavifau-
tions about birds in this volume show different ap- na.Theareaisfarawayfromthecapitalcityandcen-
proaches to this situation. Graham Tebb, the “guar- tralregionsandlackedanyresearchinfrastructurefora
dian”oftheLaGambabirdlist(SAUBERERetal.2007), longtime.Incontrast,inotherareaslikeMonteverde
meticulously describes the state of the bird inventory
(NADKARNI & WHEELWRIGHT 2000), La Selva (MC-
and presents an updated checklist for the area, which
DADEetal.1994)andLasCruces(e.g.,BORGELLAJr.et
outlinesrecentchangesindistributionareasanddocu-
al.2001),whereresearchfacilitatedbyOTS(Organisa-
mentsthestatusofrarities,migrantsandresidentbirds.
tion of Tropical Studies) has a long history
Christian H. Schulze and Isabell Riedl quantify in a
(BURLINGAME2002),ornithologicalstudiesrepresenta
comparative approach how countryside habitats con-
substantial proportion of the local research activities
tributetothehighregionalbirdrichness.Thisbaseline
(e.g.,BLAKE&LOISELLE2000,SEKERCIO LUetal.2002,
studyontheimportanceofdifferentlandscapecompo-
2007,WHEELWRIGHTetal.1984).AsoutlinedbyTEBB
nents for maintaining bird species richness in the re-
gion of La Gamba provides important information for (thisvolume)andAUBRECHT(thisvolume),collectors
andprofessionalresearchersonlyvisitedtheregionvery
theinterdisciplinarycorridorproject(describedinthis
infrequently,resultinginverylittleandscatteredinfor-
volume). Gerhard Aubrecht tries a museological ap-
proach in describing the research history and the mationavailableontheavifaunaofLaGambaandits
known museum specimens of the endemic black- vicinity(CHAVESetal.2005).Itwastheestablishment
cheeked ant-tanager (Habia atrimaxillaris) in an exem- of the La Gamba Tropical Station in 1993 which fo- Stapfia88,
plaryway.Inthisintroduction,wethereforewishonly cusedinterestonscientificstudiesincludingtheavifau- zugleichKatalogeder
oberösterreichischen
tohighlightsomeimportantaspects,withoutrepeating na of the region. The first ornithological publications Landesmuseen
NeueSerie80(2008):
thecontentsofthespecialcontributions. concerning La Gamba focused on hummingbird-plant
349-351
© Biologiezentrum Linz/Austria; download unter www.biologiezentrum.at
interactions(KASTINGER&WEBER1999,2000).Apop- dynamic of bird assemblages, permanent bird census
ular booklet (SAUBERER et al. 2007) about the birds of points should be established covering all the major
theGolfoDulceregionprovidedsomefirstimpressions habitat types within the region (primary forest, forest
of bird habitats and species richness, and the first pre- margin, gallery forests, and countryside habitats). The
liminary checklist for the regional avifauna. The first resulting data could be used to quantify how temporal
diploma theses with ornithological contents were re- dynamicofbirdassemblagesareaffectedbyhabitattype,
cently completed (RIEDL 2008, SEAMAN in prep.). In changes in land use and the appearance of range-ex-
2001,GhiselleAlvoradovisitedtheareatocollectbirds pandingoreveninvasivespecies.
fortheNationalMuseuminSanJosé.However,thepe-
Acomparisonoftheavifaunaofexistingreserveson
riod of ornithological research and documentation in
the southern Pacific slope of Costa Rica with baseline
theregionofLaGambaisstillveryshort.Therefore,it
studies on population densities of endangered species
seemsnecessarytopointoutexistinggapsinourknowl-
wouldprovideimportantinformationabouttheextent
edge and to emphasise the necessity for further studies
towhichtheseprotectedforestareascomplementeach
ontheregion’sbirdfauna.ThevicinityoftheTropical
otheronaregionalscale.
StationLaGambaoffersanopportunitytostudyforest
bird communities in one of the last existing lowland Thearearepresentsoneofthelastremaininglarge
rainforestareasonthePacificsideofCentralAmerica. blocks of evergreen lowland rainforest on the Pacific
slopeofCentralAmerica,providingauniqueopportu-
Biogeographically,theGolfoDulceregion–withits
nity for synecological studies on bird communities of
still remaining lowland rainforests – is described as iso-
thisecosystemtype.
lated in Costa Rica by JANZEN (1983), but better con-
nected to the adjacent Panama. Historical and recent Furthermore,anintactgradientofforesttypesrang-
land use transformed vast stretches of rainforest along ingfrommangroveandcoastalforesttolowlandrainfor-
thePacificcoast,whichhadlargeimpactsontheavifau- est is available for studying differences in species com-
na.ThenearbyOsaPeninsulaontheotherhandseems positionbetweenforesttypesandnichepartitioningof
further isolated, being only connected by a relatively forestspecies.
smallisthmus(KAPPELLEetal.2002).Inabroadersense,
Thediverselandscapematrixoflowlandrainforest,
theregionisinterestingasatransitionzoneandmelting
riparianforeststripsandhuman-modifiedhabitatspro-
potofbothnearcticandneotropicalavifaunas.Further-
videsanopportunitytostudytheimportanceofdiffer-
more, it is classified as the endemic bird area “South
ent land use systems for maintaining species richness,
Central American Pacific Slope” (STATTERSFIELD et al.
particularlyofforestbirdsandendemicspecies,andin-
1998)andcontainsrecognisedareasforthreatenedbirds
teractions between closed forest bird communities and
in the neotropics (WEGE & LONG 1995), particularly
adjacenthuman-modifiedhabitats.Whileforacertain
“Rincón”,“Golfito”and“RíoCoto”withtheprotected
fractionofforestbirds,countrysidehabitatsmayrepre-
areas “Corcovado National Park”, “Golfo Dulce Forest
sent ecological sinks or traps, certain land use systems
Reserve”and“GolfitoFaunalRefuge”.Thus,theregion
(e.g.agroforestrysystems)mayprovidevaluablesecond-
isofoutstandingimportanceforbirdconservation.The
ary habitats for others, or at least stepping stones for
endemic birds and species with limited distributions of
movementsbetweenforestfragments.
specialinterestaredescribedbyTEBB(thisvolume).
There are still many gaps in our knowledge about
From the situation described above, some conclu-
the autecology and biology of species. Breeding times,
sions can be drawn about where future ornithological
breedingecology,andseasonal(altitudinal)movements
researchcouldfocus:
still need to be studied. Especially interesting are the
ThespeciesinventoryofLaGambaisstillfarfrom distinct Caribbean and Pacific distribution patterns of
beingcomplete.Therefore,afurtherdocumentationof (sub)specieswhichmightrevealfurthernewsystematic
birdrecordsfromtheareaishighlyrecommended.This results as recently shown with Cherrie’s tanager (Ram-
wouldnotonlyimprovethecompletenessofthebirdin- phocelus costaricensis) and Passerini’s tanager (Rampho-
ventory but would allow us to document temporal celuspasserinii).
changesofbirdspeciescompositionandtheoccurrence
Specialhabitatsliketheseacoast(marinebirdsand
of individual species. Several species expanding their
waders) and mangroves are still poorly investigated.
rangesnorthwardsorsouthwardsalongthePacificslope
Two species of special interest, the threatened and en-
have recently reached La Gamba and others will cer-
demic mangrove hummingbird (Amazilia boucardi) and
tainlyfollow.
thethreatenedyellow-billedcotinga(Carpodectesanto-
Foramoredetaileddocumentationofthetemporal niae)arerestrictedtomangrovehabitatsandneedspe-
350
© Biologiezentrum Linz/Austria; download unter www.biologiezentrum.at
cialattention.Theconservationstatusofbothspeciesis MCDADEL.A.,BAWAK.S.,HESPENHEIDEH.A.&G.S.HARTSHORN(ed.)
incompletelyknown.Moredetailedstudiesonthebiol- (1994):LaSelva.Ecologyandnaturalhistoryofaneotrop-
icalrainforest.—Univ.ChicagoPress.ChicagoandLondon.
ogyofsuchspecieswithhighconservationrelevanceare
urgently needed to develop efficient conservation NADKARNI N.M. & N.T. WHEELWRIGHT (ed.) (2000): Monteverde.
Ecologyandconservationofatropicalcloudforest.—Ox-
strategies. Habia atrimaxillaris is another species with a
fordUniv.Press.NewYorkandLondon.
highconservationvaluetoithighlyrestricteddistribu-
RIEDLI.(2008):GalleryforestsinthelowlandcountrysideofCos-
tionrange(seeAUBRECHT,thisvolume).Therainforest taRica:Corridorsforforestbirds?—Diplomathesis,Univ.
ofLaGambaholdsoneofthelastlargepopulationsof Vienna.
thespecies,providingarareopportunitytostudyitslife
SAUBERERN.,TEBBG.,HUBERW.&A.WEISSENHOFER(ed.)(2007):The
historyandpopulationdensity. birdsoftheGolfoDulceregion,CostaRica.—Vereinzur
FörderungderTropenstationLaGamba,Vienna.
Seasonal movements directly lead to the problems
EKERCIO LUC.H.,EHRLICHP.R.,DAILYG.C.,AYGEND.,GOEHRINGD.&
oflandscapefragmentation.Whichspeciescanadaptto
R.F.SANDI(2002):Disappearanceofinsectivorousbirdsfrom
these changes and which populations act as ecological tropicalforestfragments.—Proc.Natl.Acad.Sci.USA99:
sources or sinks? How do rapid and/or long-term 263-267.
changes in land use influence bird communities? How EKERCIO LUC.H.,LOARIES.R.,OVIEDOBRENESF.,EHRLICHP.R.&G.C.
dobirdcommunitiesandspeciesreacttotheestablish- DAILY(2007):PersistenceofforestbirdsintheCostaRican
mentofecologicalcorridorsandhowcantheeffectsof agriculturalcountryside.—Conserv.Biol.21:482-494.
natureconservationbemeasuredbymonitoringstudies? STATTERSFIELDA.J.,CROSBYM.J.,LONGA.J.&D.C.WEGE(1998):En-
demic bird areas of the world. Priorities for biodiversity
Allthesequestionsoffermanypossibilitiesforfuture conservation.—BirdLifeConservationSeries7:1-846.
ornithological research in the La Gamba region. The
WEGED.C.&A.J.LONG(1995):Keyareasforthreatenedbirdsin
TropicalStationLaGambaoffersanincreasinglyuseful theneotropics.—BirdLifeConservationSeries5:1-311.
infrastructure, a scientific focal point and a starting WHEELWRIGHTN.T.,HABERW.A.,MURRAYK.G.&C.GUIDON(1984):
point for ornithological investigations. Any scientific Tropicalfruit-eatingbirdsandtheirfoodplants:asurveyof
collaborationisverywelcome. aCostaRicanlowermontaneforest.—Biotropica16:173-
192.
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