The Delta of the Iscuandé River is located in the northwestern Pacific coast of Colombia, Nariño Department, on the border with the Cauca Department. Several islands that formed through the siltation process of the Iscuandé River constitute the area. Coastal environments such as sandy beaches, muddy plains, and mangroves are representative of the area. Most of these ecosystems are important for waterbirds, especially seabirds and shorebirds that use them as resting and breeding grounds. The Delta of the Iscuandé River is part of the Sanquianga National Park buffer zone, which has an extension of 89,000 hectares (219,750 acres), and is a protected area managed by the government of Colombia. The park maintains the best preserved mangroves in this area of the Pacific coast. The climate in the whole region is tropical humid and precipitation reaches 7,000 millimeters per year.
Birds and other wildlife
The site holds up to 25% of the continental population of Charadrius wilsonia and 1% of the hemispheric population of Actitis macularia. It is estimated that this site is used annually by about 50,000 shorebirds.
The area has strategic importance for shrimp fishery (the main economic activity in the region) and fish flour production from small fishes that local people catch. It is important to highlight that during the second half of the year, an endangered sea turtle species, Lepydochelis olivacea, uses these beaches as nesting sites.
This area is characterized by high tectonic activity, as is the rest of the Pacific coast of Colombia, because it is located along the "Pacific Fire Belt". The area is therefore eventually affected by earthquakes. The last big event took place in 1979 when a tsunami affected the whole area and destroyed several coastal villages.
The towns of Ensenada and Juanchillo are located in front of the Delta of the Iscuandé River. These two villages are inhabited by around 500 people who base their livelihood on shrimp fishery and the gathering of a mangrove bivalve (locally known as "Piangua”). Per capita income of the population is very low, therefore these settlement are very poor, and basic sanitation services are deficient.
Conservation and Ecology
The Delta has a strong influence of the Pacific Ocean tidal regime; the difference between high and low tide is 4.3 meters. The siltation process generated by the Iscuandé River has produced several sandy-muddy islands that have consolidated through time and are used by birds. The area hosts several coastal environments such as sandy beaches, muddy plains, and mangroves. Most of these ecosystems are important for waterbirds, especially seabirds and shorebirds that use them as resting and breeding grounds.
The area is a resting and feeding site for seabirds such as Pelecanus occidentalis, Sula nebouxii, Sula leucogaster, Phalacrocorax brasilianus, Thalasseus maxima, Leucaphaeus atricilla,and Leucophaeus pipixcan. A breeding colony of P. brasilianus is located in the Bocana Iscuandé area. The zone also provides breeding grounds for the shorebirds Charadrius wilsonia beldingi and Haematopus palliatus. The herons Nyctanassa violacea and Nycticorax nycticorax are present but there is not evidence of reproduction yet. High concentration of egrets and herons is very common: Egretta thula, Ardea alba, Ardea cocoi, Egretta tricolor, Egretta caerulea. Egretta rufescens and Ardea herodias are sporadically present in smaller numbers. Furthermore, approximately 150 pairs of Gelochelidon nilotica breed in the area, constituting the largest documented reproductive colony of this species in Colombia. There is also the presence of other migratory birds, such as Anas discors, Seiurus noveboracensis, Contopus sp. and Doliconix oriziborus. Land birds associated with the surrounded vegetation are Quiscalus mexicanus, Amazilia tzacatl, Tyrannus melancholicus, Dendroica petechia, Coccizus melacorryphus, Crotophaga ani, Hirundo rustica, Laterallus sp.
Other fauna that has not received research attention yet are the reptiles and amphibians Basiliscus galeritus, Bufo marinus, Boa constrictor, Iguana iguana, Bradypus sp.,and Noctilius sp. This site is also used by the endangered sea turtle “Caguama” (Lepydochelis olivaceos) as a nesting area.
There are two major threats to the site. One is related to solid waste disposal, which is carried to the area by the river and accumulates on the beaches. The human population growth “upstream" and the absence of a proper waste disposal system have lead to this pollution because all the wastes are thrown into the river and then carried to the sea. The other major threat is the increase of sediments being deposited during low tide as a result of upstream deforestation, caused by different extractive human activities.
Disturbance is mainly caused by urban expansion and changing consumption habits among populations living in the main city near the area. Increasing populations add to the problem of an inadequate waste collection and disposal system, causing increased accumulation of solid waste on the delta beaches. This problem also affects the breeding colonies of Ch. wilsonia, which are running out of available space for nesting. The increased presence of dogs and cats in La Cunita and Quiñónez areas are also a source of disturbance for birds using habitat near some settlements (Juanchillo y Ensenada).
Furthermore, land conversion along river banks for agricultural purposes has increased the quantity of sediments that are deposited in the low tide zone. Another aspect is the collection of bird eggs by local people to supplement their diet, in addition to capturing chicks as pets.
The development of a waste management system and a sanitation plan is critical for the closest communities to the site (Juanchillo y Ensenada), which together have a population of 500 people approximately. Another important area of work is to influence the municipal planning so the Land-use Zoning Plan considers this area as a Conservation Area and regulates any urban development plan.
The Calidris Association has been working in the area since 2004, where it conducts regular seabird and shorebird censuses as well as shorebird banding. They have also carried out studies on the trophic ecology and reproductive monitoring of Gelochelidon nilotica and Charadrius wilsonia.
Asociación Calidris. 2003. Programa de monitoreo de aves acuáticas en Parques Nacionales del Pacífico Colombiano. Technical report. Fondo para la Acción Ambiental, UAESPNN Territorial Suroccidente, Cali.
Casas, P. A. 2005. Seleccion de habitat de anidación y formacion de colonias del Gaviotín Blanco Sterna nilotica (Aves: Laridae) en el Parque Nacional Natural Sanquianga, Pacifico colombiano.Undergraduate thesis. Universidad del Valle, Cali.
Casas, P & R. Johnston. Animación del Gaviotín Piquigrueso (Sterna nilotica) en el Parque Nacional Natural Sanquianga, Pacífico colombiano. Boletin SAO. (En prensa)
Galbraith, C.A. & Stroud, D.A. (eds). Waterbirds around the world. The Stationery Office, Edinburgh, UK.
Johnston-González, R., Ruiz-Guerra, C. J., Hernández, C. E., Castillo, L. F. & Cifuentes-Sarmiento, Y. 2006. Sturnella bellicosa sigue aumentando su distribución en Colombia. Orn. Colombiana 4: 64–65.
Johnston-González, R., L. F. Castillo, C. Hernández, C. Ruiz. 2006. Whimbrels roosting in Colombian mangroves. Wader Study Group Bulletin 110:63
Johnston-González, R., C. J. Ruiz-Guerra, C. E. Hernández, L. F. Castillo, Y. Cifuentes Sarmiento. 2006. Sturnella bellicosa continúa expandiéndose en Colombia. Ornitología Colombiana 4:54-55.
Johnston-González, R., C. J. Ruiz G., L. F. Castillo & C. E. Hernández. 2006. Colombia revisited, a regional important site for shorebirds on the Pacific coast of South America (Abstract). Wader Study Group bulletin (109):58.
Naranjo, L. G., L. F. Castillo, R. Johnston-González, C. E. Hernández, C. J. Ruiz G., F. Estela. 2006. Waterbird monitoring and conservation in Protected Areas of the Colombian Pacific. Pages: 177-180 Boere, G.C.
Ruiz, C. J. 2004. Distribución espacio-temporal y comportamiento de aves playeras en el Parque Nacional Natural Sanquianga (Nariño, Colombia). Undergraduate thesis. Universidad del Atlántico, Barranquilla.
Ruiz-Guerra, C., Y. Cifuentes-Sarmiento, C.E. Hernández-Corredor, R. Johnston-González & L. F. Castillo-Cortés. 2008. Breeding of two subspecies of Wilson’s Plover (Charadrius wilsonia) on the coasts of Colombia. Ornitología Colombiana No.6.
Ruiz-Guerra, C., Richard Johnston-González,Yanira Cifuentes-Sarmiento, Felipe A. Estela, L. Fernando Castillo, Carlos E. Hernández & Luis G. Naranjo. 2007. Noteworthy bird records from the southern Chocó of Colombia.Bulletin B.O.C. 127(4)
Ruiz-Guerra, C. J. & Johnston-González R. 2006. Habitat use, seasonal dynamics and behavior of shorebirds wintering in the southern Pacific coast of Colombia (Abstract). Wader Study Group bulletin (109):53
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Photos and map courtesy of Asociación Calidris
Enjoy this brief new video about Delta de Iscuandé WHSRN Site on YouTube. In Spanish with English subtitles.
In November 2011, Asociación Calidris and the “Esfuerzo Pescador” Community Council signed a Conservation Agreement. This initiative is designed to promote actions that improve environmental conditions on 12,000 hectares of the community's lands, 4,000 of which comprise the Delta de Iscuandé WHSRN Site of Regional Importance. A short video about the Conservation Agreement from the community's perspective is available (in Spanish) on YouTube.
"Vivir mejor para conservar": A short article about how the WHSRN Site designation has helped support efforts to improve the quality of life for Delta de Iscuandé communities. A special note from Asociación Calidris (in Spanish).
An overview video about Delta del Rio Iscuande is available on YouTube.
The Colombian Pacific area is mostly inhabited by communities of African descent, which through the Colombian Constitution of 1991 were recognized as an ethnic minority group. The Constitution also created an ethnic and territorial entity or Community Organization invested with local authority rights called Community Council. Among its main activities are land zoning and adequate use of natural resources. The Community Councils play a very important role in all actions and decisions taken in relation to the territory, therefore their participation is fundamental in conservation processes. The Delta of the Iscuandé River is regulated by the Esfuerzo Pescador Community Council. They have been participating since 2007 in different activities aimed at raising awareness about the importance of the site for shorebirds, which they fully support.
The first Colombian Pacific Coast Migratory Bird Festival took place in October 2008. This event is aimed at raising awareness about the importance of the Pacific coast for migratory bird species such as shorebirds, as well as for sea turtles. It is hoped that this festival will become a tradition for the local community.
Esfuerzo Pescador Community Council
Telephone (cell): 312 7979288
Santa Bárbara de Iscuandé Municipal Council
Telephone (cell): 313 65001675
Luis Fernando Castillo
Director, Asociación Calidris
Carrera 24 Nº 4 – 20 Piso 2
Cali - Colombia
Teléfono (+ 57) 2 5560455