by Lenin Riquelme, Ramón Alvarado, José Armando Palma, Fundación de Parques Nacionales y Medio Ambiente (Fundación PA.NA.MA.); Eustaquio Araúz and Kerzon Ruiz, Asociación de Amigos y Vecinos de la Costa y la Naturaleza (AAMVECONA) Existing data for Antillean manatees is scarce making it difficult to make well informed management decisions both regionally and locally. In Panama´s Caribbean Coast, the first systematic manatee distribution and status surveys took place in 1987. Almost two decades later, a team of Panamanian researchers is conducting a new survey to know the current status of the manatee population and the impacts of old and new threats, educating the local population on the specie’s biology and conservation and pursuing the establishment of a long-term research and conservation program. The project has focused on the San San, Changuinola and Sixaola river systems,where manatee counts have been highest in the past. Based upon the number of aerial sightings and boat and ground reconnaissance trips, it seems the manatee population of this particular area has increased. Threats increased also, particularly the recurrent discharge of solid waste and polluted water, extensive cattle ranching and, more recently, ill-planned coastal development. and hidro-energy production projects. Local communities have managed to establish a water quality and wetland protection program that strongly pertains to manatee conservation. In the coming months, the survey will continue in suitable habitat to cover the entire local manatee range.
The Antillean Manatee is a member of the Trichechidae Family and belongs to the Order Sirenia that includes the Dugongidae Family, represented by the Dugong (Dugong dugon) and the extinct Steller´s sea cow (Hidrodamalis gigas). The Trichechidae Family includes three species of manatee, all distributed in tropical and sub-tropical areas along the Atlantic coast and adjacent rivers: the West African manatee (Trichechus senegalensis), Amazonian manatee (Trichechus inunguis) and the West Indian manatee (Trichechus manatus). In 1986, Domning and Hayek demonstrated that there are two sub-species of West Indian manatee, the Florida manatee (Trichechus manatus latisostris) and the Antillean manatee (Trichechus manatus manatus), probably as a reflection of reproductive isolation brought on by the intemperate northern coast of the Gulf of Mexico and characteristically strong currents found in the Straits of Florida. (Domning, D.P. and L.C. Hayek, 1986).
The Antillean manatee has the largest range of Sirenia, found throughout the greater Caribbean area, including southern Texas, Mexico, Central America and northeastern South America. The sub-species´ distribution is uneven due to the patchiness of suitable habitat as it requires both vegetation (sea grasses, mangroves, water hyacinths and other fresh and brackish water plants) for food as well as a source of slow-moving fresh water (Reynolds, J.E. III. 1981). The highest population densities are found where these essential resources exist and there is no or little human presence; regionally it seems the highest numbers are found in Belize (300 – 700) and Mexico (400 – 800), with accounts for Central American countries being less than 200 total and practically unknown populations in South America (NRCA/UNEP 1994). These small numbers and particularly the species´ very slow breeding cycle, together with habitat destruction (coastal development, agriculture, draining of wetlands, pesticide runoff), accidental deaths (drowning in fishing nets, watercraft collisions) and poaching are the main reasons why the Antillean manatee is listed as vulnerable in IUCN´s Red Data Book (2000) and CITES Appendix I as threatened with extinction1. In Panama they have a protected status since 1967.
Quantitative information on Antillean manatee is limited, although historical accounts indicate they were once more common; hunting has been responsible for declining numbers throughout much of their range (Lefebvre et al., 1989). Until the early 1990´s, it´s distribution and abundance had been spottily documented. In 1995, UNEP-SPAW´s promoted the establishment of a Regional Management Plan for the Antillean Manatee that has encouraged further research and the establishment of national manatee conservation plans2.
In Panama, available information about the manatee and its ecology is based upon information from interviews, anecdotes from informants and overflights with the purpose of determining the presence of the species along the Panamanian Caribbean coast (Montgomery, G.B., N.B. Gale, and Murdoch, Jr. 1982; O´Shea T.J., 1981, Mou Sue, L.L. et.al, 1990). Mou Sue´s survey, conducted in 1987 through Fundación PA.NA.MA. and the US Geological Survey´s Sirenia Project, is the only extensive study available. It accounted for 71 sightings in 25 overflights, with the population ranging 42 – 72 individuals. The study established that manatee habitat in Panama ranges from San San Pondsak Wetlands down to the Peninsula Valiente, including the lower watershed of the Sixaola, Changuinola, Mananti, Guariviara, Cricamola and Cañas rivers and the Jugli and Damani lagoons; the survey also included the introduced manatee population at Gatun Lake, within the Panama Canal area. In addition, field expeditions, community surveys and overflights in Calovébora, Coclé del Norte and Miguel de la Borda rivers and the San Blas coastal strip indicated the presence of the species but no sightings took place.
Explosive coastal development around manatee habitat in the last 10 years made necessary this study in order to assess the impact such development may have had on the species´ condition, number and habitat. Since September 2004, a research team formed by Lenin Riquelme, José Armando Palma and Ramón Alvarado, from Fundación PA.NA.MA. and Eustaquio Araúz and Kerzon Ruiz, from the local settler organization AAMVECONA, has been conducting a manatee conservation project. It consists in a survey to know the current status of the manatee population and the impacts of old and new threats and environmental education on the specie’s biology and conservation, as part of the establishment of a long-term research and conservation program. Work has focused on the San San Pondsak Wildlife Sanctuary and adjoining wetlands-- San San, Negro, Sixaola and Changuinola rivers, Changuinola lagoons and Soropta Cove, located in Panama´s Bocas del Toro region. This final report is based on the results obtained in that particular area.
To collect scientific information on the number and status of Panama´s manatee population in order to a) contribute with reliable data to update the Regional Conservation Plan for the Antillean Manatee of the Convention for the Protection and Development of the Marine Environment of the Wider Caribbean Region (NRCA/UNEP) and its Caribbean Environmental Plan, under the framework of the Convention for Biological Diversity and b) update local environmental management authorities and institutions so that informed decision-making leads to effectively protect the local stock.
Research methodology consists of four components: Aerial survey overflights, Interview surveys, use of Geographic Information Systems (GIS), On-Site Assesment of Suitable Habitat and Tagging. The aerial survey overflights where conducted aboard a 4-passenger Cesna 170B flying at a speed of 120 – 150 km/hr at an average height of 150 meters. The purpose of such overflights was to determine if there is any variation in population during the year as well as to account the highest possible amount of individuals to determine the minimum current population of manatees.
The team´s original plan was to conduct extensive 4-6 hour overflights covering the entire area from San San Ponsak Wildlife Sanctuary to the Juglí and Damani lagoons and, depending on the densities found, to conduct short flights in specific sites and make use of landing strips located near manatee habitat and communities. However, weather conditions turned extensive flights impossible given the extremely strong winds and heavy rains, landing in local strips became dangerous. Only modern airport facilities, namely the Changuinola and Bocas del Toro Island airports, could be used under good weather conditions.3 Given these bad weather conditions, it was decided that short overflights should be conducted within a specific research area so as to take advantage of good weather while reducing the level of danger for the research team. A total of nine 2-hour overflights were conducted, three in December 2004, three in February 2005 and another three in April 2005, all focused on the San San Pondsak Wildlife Sanctuary and adjoining wetlands--San San, Negro, Sixaola and Changuinola rivers, Changuinola lagoons and Soropta Cove, all located in the province of Bocas del Toro4.
Before beginning an overflight, the research team designed a plan to select the specific zones where flights should concentrate and what other areas should be observed as possible manatee habitat. The route was drawn on a cartographic sheet. When manatees were sighted, the plane circled around in order to obtain a better vision and a more precise count of the individuals that emerge and submerge since they can be confused with the ones on the surface.X A standardized data collection sheet was used to keep a reliable count of manatees which included information such as amount of animals detected, exact site, behaviour of the individual, state of growth (adult, juvenile, calf) and sex (male, female), weather and water conditions. Two team members participated in each flight: the main observer next to the pilot and the secondary observer on the rear seat.
Boat and ground assessments were conducted at the San San river and the lower watersheds of the Sixaola and Changuinola rivers and the adjoining coast. During ground recoignaissance, the team relied on local wooden and fibreglass boats as means of transportation. This activity allowed detecting the main spots where manatees gather, feed or reproduce, determine the different types of vegetation they consume and conduct interviews in hard-access areas. The interview surveys were conducted among fishermen and dwellers living on the nearby waterways since their activities and closeness to the water allows them to keep continued contact with the aquatic and marine environments, and also aircraft pilots who make daily flights in the area. The questionnaire for these interviews were drawn from O’Shea, T. et. al. 1986 report on the status and distribution of manatees in Venezuela that focuses on general and particular knowledge on the interviewee and includes three main sections: distribution and abundance, history and biology, culture and tradition.
Originally it was planned thata minimum of 10 individuals found in different locations would be tagged using a tagging assembly, developed by the U.S. Geological Survey, that includes a rubber peduncle belt and a tethered floating platform transmitter terminal (PTT). The 39 x 9 cm-diameter transmitter housing contains satellite, VHF, and ultrasonic transmitters that provide information about the individual´s movements and location, enabling the research team to locate feeding areas and, probably, more individuals. The techniques used for catching free-ranging manatees that pose the least risk to their health and life are the land sets and open water captures, that should be used according to the setting. Using land sets, manatees might be captured in the water channels and coastal lagoons using a 150 m long x 10 m deep net. Once close to the manatee, a net is pulled manually behind the animal, pursing it in the net, and hauling it to shore. This technique requires 15 people in order to handle the animal properly. The open water capture technique consists on deploying from a 6-m boat while circling manatees in open water. The manatees are then pursed in the net and pulled on board. This method requires 8 people and enables researchers to catch random animals as well as specific individuals multiple times.
These techniques are designed to minimize any possible negative impact on individual manatees. Nevertheless, there are numerous obstacles and impediments to keeping manatees tagged over the course of a study as they are designed to avoid any physical damage or difficulty in their “normal” life. The USGS-designed tags require that transmitter batteries be replaced every 6 months; a snorkler has to quietly approach a manatee and change the transmitter on the distal end of the tether. Individual animals vary on their tolerance to tag exchanges. Damage to transmitter housings may occur from boat strikes and caiman bites, causing complete tag loss or loss of function from water intrusion. People may pull tags off. Algal and barnacle growth may interfere with function and cause some tag loss. It is expected that some Manatees will lose their tags and will have to be retagged. Advice from Belize-based manatee researchers pointed out that tagging should take place when the research program has further advanced. Thus, it was decided the tags would be purchased but tagging will take place when electronic tracking equipment (namely a computer, tracking software and replacement batteries) are available, as well as the level of institutional and local community involvement and the funding.5
Currently, the research team is making use of Geographic Information Systems (GIS) to produce precise, digitised maps, plotting geographically referenced data sets: location of manatees, distribution and density of fresh water macrophytes, sea grasses and mangrove stands, boat traffic patterns, location of run-off water discharges, current and proposed development sites and so forth. The data will be plotted in overlays that allow visualization of locations where current and future human activities might have a substantial impact on manatees. Identification of these sites will permit the appropriate agencies and local communities to take the steps to reduce or mitigate impacts.
Part I: Abundance and Distribution
The research area is located in the Panamanian province of Bocas del Toro, near the towns of Changuinola and Almirante, at Coordinates ~09º30'N 082º30'W, specifically in the lower watersheds of the San San, Sixaola and Changuinola river systems and Soropta Cove. The area provides crucial habitat for the conservation of 133 bird species of which 36 are threatened including Amazona achrocephala, Cairina moschata anf Dendrocygna autumnalis. There are 55 species of mammals of which 24 are threatened including Agouti paca, Hydrochaeris hydrochaeris, Mazama americana, Trichechus manatusmanatus and 54 species of reptiles of which 7 are threatened. Reptiles include Caiman crocodilus, Caretta caretta, Chelonia mydas, Dermochelys coriacea and Eretmochelys imbricata. There are 20 species of amphibians. The wetlands are a very important habitat for palustrine and marine birds (Castillo 1991).
Most of the research site lies within the San San Pondsak Wildlife Sanctuary, a RAMSAR site. It is an aggregation of channels and shallow brackish and freshwater lakes in the lower basin of the Changuinola and San San Rivers. Other habitats include coastal plains and bays formed by the accumulation of sand in littoral strands with sandy beaches and bars along the coast. There are mangroves and an 80 sq km peat swamp. There are five types of vegetative associations. On the coast, Chrysobalanus icaco and Coccoloba uvifera, followed by Hibiscus tiliaceus dominate the association. In the transitional areas, there is Cocos nucifera and Terminalia catappa. In the mangroves Avicennia germinans, Conocarpus erectus, Laguncularia racemosa, Pelliciera rhizophorae, Rhizophora harrisonii and R. mangle occur. In the Cativo association Prioria copaifera in association with Raphia taedigera occurs. The Orey association is characterised by Campnosperma panamensis and the Cerillo-Sangrillo association by Pterocarpus officinalis and Symphonia globulifera (Castillo 1991).
The lower San San, Sixaola and Changuinola river sistems recharge aquifers which provide water for human consumption and use in the banana plantations. It also traps sediments, therefore improving water quality and reducing the effects of coastal erosion. The geomorphology is characterised by coastal plains and lowlands formed by the accumulation of sand in coastal bands. There are sand and barrier beaches (the mouth of the Río San San). The hydrological areas are defined by the Río Changuinola (with a basin of 2,810 sq km and with a flow of 4,168 cubic m/sec in 1963) and the Río San San. These rivers flow into the Caribbean.
The bedrock consists of intrusive and extrusive metamorphosed igneous rocks. Sedimentary rocks including limestone and conglomerates are found in the lower areas as well as in the river valleys, on the shore and on the islands. This material is mainly from the Tertiary and the Quaternary periods. The clay soils with slow infiltration are acidic with a low content of organic material. The climate is humid tropical with an annual precipitation of 2,000 mm and with a high ambient humidity the year round. The annual average temperature varies between 18°C and 34°C along the coast.
The landscape has been shaped and impacted by human activities and settlement, particularly major agricultural operations by the United Fruit Company. Since the early XX century, the company established more than 5,000 hectares of banana plantations that required building of irrigation and runoff discharge channels, the settlement of workers in several communities or “fincas” and the use of large amounts of pesticides. The most recent concerns within the site focus on the expansion of areas used for ranching and, to a lesser extent, subsistence agriculture and pig raising. Other concerns are the hunting pressure on small mammal and bird species, many of which are endangered, apparent over-harvesting of fish, lobsters and (illegally) sea turtles for subsistence, and extraction of firewood and timber for boat and house-building.
Sixaola river: Its watershed covers 2,848.3 square km (531.5 in Panama and 2,316 in Costa Rica), from the 3,800 heights found in the Talamanca Range to the floodplains on the Caribbean coast. Part of the river sets the Caribbean border between Panama and Costa Rica. North of the river mouth, within Costa Rica, there is a protected area known as Gandoca-Manzanillo that has similar characteristics to San San Pondsak´s and provides sanctuary to a manatee population.
San San river: The San San river, of 37,3 kilometers in length, is the main component of the river basin that forms the rivers that are between the Changuinola and the Sixaola, It is a river of little depth that, when meeting with the sea it forms one sand bar and an inner coastal lagoon. This slow flowing river is mostly located within the San San Pondsak Wildlife Sanctuary, including its tributary the Negro river. The river receives most of the runoff from the large banana plantations and cattle ranching operations that develop around the protected area. Water discharges increase during the rainy season and the impact of the chemicals it contains can be seen along the discharge channels known as Bomba A and Bomba B, with large numbers of dead fish and shrimp floating in the waters.
Changuinola river: the main course of the Changuinola river as well its tributary the Teribe are relatively fast flowing courses. The lower course of the river changed in the early XX century when the United Fruit Company re-routed the river flow to a location to the south. The natural course became a series of interconnected lagoons known as Changuinola lagoons that still remain connected to the river. Re-channelling work also included digging another channel, located south of the river mouth, known as Soropta Channel, a narrow 8-meter wide 15-km long ditch that reaches the sea in front of Isla Colon. The Soropta Channel is completely unpopulated but it´s an important route for boats moving soutward from the Changuinola to the coast.
Soropta Cove: Located at about 10 km from the mouth of the Changuinola river and facing Isla Colon´s Boca del Drago area. It is a shallow water area of pristine coral reefs, and patches of sea grass (Thalassia sp). fringed by mangrove forests.
Summary of Manatee Sightings
November 4, 2004;
10:00 am – 12 noon
1 sited where the Negro river joins the San San; 1 by a runoff channel known as Bomba A that joins the San San; 1 by the runoff channel known as Bomba B that also joins the San San.
November 30, 2004;
10:00 am – 12 noon
3 adults sighted at Soropta Cove.
February 5, 2005;
10.00 am – 12 noon
9 adults and 4 calves gathered at “La Olla”, a lagoon by the mouth of the San San river.
February 8, 2005,
10.00 am – 12 noon
1 adult at Soropta Channel; 7 adults and 2 calves in the Changuinola lagoons specifically in a site known as Quebrada Lagarto.
April 9, 2005
4:00 pm – 6:00 pm
7 adults and 2 calves at “La Olla”.
April 20, 2005
4.00 pm – 6.00 pm
9 adults and 2 calves along the Soropta Channel.
The number of manatees sighted in each site was quite significant as compared to the 1987 survey. Mou Sue´s 1987 survey provided a total of 42 manatee sightings in 13 overflights within the same area in 8 months, with a rate of 81.8% probability of sighting a manatee during an overflight. The present survey recorded 49 sightings in 6 overflights in 3 months with a 100% probability rate. In terms of reproduction, the 1987 survey recorded 5 calves while 9 were sighted during the present study, with a frequency of 11.9% in 1987 and 18.3% in the present study.
T Foto R Alvarado, 2004 he San San, its tributary the Negro river and its man-made channels seem to be the main manatee habitat in the area; the largest single sighting took place at “La Olla”, near the mouth of the San San, where gatherings of 13 and later 9 individuals was found. This number is exactly the same highest amount in Mou Sue´s study, who recorded 8, 9 and 13 sightings within the San San in three different dates, indicating most of the sightings took place at “La Olla”. It seems manatees migrate up river taking advantage of high tides, entering the Negro river, Bomba A, Bomba B and an intricate web of minor channels where they can feed on freshwater macrophytes, mainly water hycinth (Euchornia crassipes) and water lettuce (Pistia stratoites) as well as true grasses such as Guinea grass (Panicum maximum) that grow on the river bank. They move down river to La Olla where they can feed on the abundant mangrove vegetation: black mangrove (Avicennia germinans L.), red (Rhizophora mangle L.) and white (Laguncularia racemosa L.). Though agrochemicals continue being dumped in the San San, there is no indication they are staying away from those areas.
The most surprising sightings took place within the Changuinola river system. The lagoons, offer excellent habitat for manatees, despite the large number of populated sites (Fincas 6, Finca 44, Finca 63, Finca 64, Finca 66 and Finca 67) found along its banks and the general use of this water course as a garbage dump. In 1963, 9 manatees where taken from this area and translocated to the Panama Canal area, giving origin to that particular population. Mou´s study recorded 1 manatee in Soropta Channel and no sightings within the Changuinola lagoons, though he reported that former hunters had counted up to 50 manatees gathering in Quebrada Lagarto, a stretch of water within the Changuinola lagoons. The research team sighted a gathering of 9 individuals in Quebrada Lagarto.
Despite local boatmen´s assertions that manatees are uncommon within the Soropta Channel because it is too narrow and shallow, 11 individuals where sighted. The high number of manatees sighted at the channel could be the result of increased waterflow from heavy rains and flooding in recent months that have widened the channel and improved its quality as manatee habitat. Quite possibly, these man-made channels could hold the largest number of manatees in Panama. Soropta Cove, rich in seagrass meadows and coral reef protection is the only marine area where manatees were found. The team sighted 3 separate adults that seemed to be feeding on the cove´s Turtle grass (Thalassia testudinum) patches and the mangrove stands. Soropta cove and other seagrass-rich coastal areas might serve not only as feeding grounds but also allow for manatees to move between these closeby river and channel systems.
Though repeated overflights included the Sixaola river, no sightings were made. The mouth of the Sixaola marks the southern tip of Gandoca-Manzanillo Wildlife Refuge that protects the lowlands of the southern Caribbean coastal region of Costa Rica. Manatee sightings in the area are scattered and include 1 in 1982 and 3 in 1990 at the coastal Gandoca Lagoon (Vasquez R. 1993 in litt.); an aerial survey in July 1991 yielded 2 sightings just north of the mouth of the Rio Sixaola (Reynolds et al. 1995). It seems this manatee population living in Costa Rica´s Gandoca Manzanillo area probably comprises a maximum of 6 and a minimum of 3 individuals connected to manatee populations living in contiguous habitats in the San San Wildlife Sanctuary within Panama (Jimenez 1998; MINAE/PNUMA 2001).
The highest number of sightings in a single overflight at San San, both in 1987 and now, remains the same; but the number of sightings at both Soropta and Changuinola lagoons have been much higher in the current survey. Looking at the dates---and knowing the manatees relatively slow speed- it is highly possible that the 13 manatees sighted on February 5, 2005 at San San (La Olla) and the 10 individuals sighted in Soropta Channel-Changuinola lagoons on February 8, 2005 are entirely different individuals, just as the 9 individuals sighted at La Olla on April 5, 2005 and the 11 sighted along the Soropta Channel on April 20, 2005. The latest sightings recorded in April indicate manatee numbers were little affected by the heavy flooding from late 2004 and early 2005. So far, no strandings have been reported from areas where the waters have receded.
Part II: Conservation
Over the years, threats to the manatees habitat has steadily shifted from those related with traditional activities (hunting, subsistence agriculture, small-scale logging) to massive forms of environmental degradation from the long-lived banana industry to extensive cattle ranching and, more recently, ill-planned coastal development and recreational activities.
Hunting remains a threat for manatees even though the old hunters have faded away and younger generations generally do not practice this activity. Field surveys and informal interviews showed that most people has never seen a manatee and the ones who have sighted them usually live a few meters away from their habitat or have accidentally seen them during boat trips. There was only one account of manatee consumption in the San San area that took place 5 years ago when a manatee was shot and the meat distributed among several families. It seems traditional hunting is no longer practiced; rather, manatees have been killed during accidental encounters with humans.
There was one report of an adult manatee being wounded by boat propellers at sea 4 years ago. Interestingly, the interviewee did not know what he had hit until he saw the picture of a manatee floating on the water; he did not know what happened to the animal afterwards. In April 2004, a dead manatee was found floating on the San San river. It was a 2.5 mt. adult, weighting around 900 pounds; it was found at a very advanced decomposition stage and there was no obvious indication on the cause of death. Incidental take of manatees in fishing nets, noted in other countries, was not reported.
Land bordering the sites includes 5,000 ha of banana plantations. Enlargement of these plantations may lead to further pollution of the Negro, San San and Changuinola Rivers. Felling of the forest still occurs in the middle part of the San San and Changuinola river basins. Discharge of chemical-laden runnof into rivers and channels is still a common occurence. Fungicides such as ethylene bisdithiocarbamates (EBDCs) and chlorothanil are commonly used in the banana fields. These substances have been proven to drift into the water, after continuous rainfall. In San San, water from the banana plantations flows towards the river through Bomba A and Bomba B. In the Sixaola and Changuinola, the channels run directly towards the rivers. Whenever these controlled discharges occur, large numbers of fish (Two-spot astianax, Banded astianax, etc.), shrimp (Macrobraquium sp) and other fresh water life forms can be seen floating along the river banks, particularly near the discharge points. The discharges do not seem to keep the manatees away from those points; studies might be necessary to know the effects the chemicals might be having on them.
The San San river system and part of the Changuinola became part of the RAMSAR list of wetlands of international importance on September 6, 1993. Earlier research, including that conducted on the manatee, encouraged the area´s designation under protected status through. Resolución No. J.D.-020-94 from the National Environmental Authority. These designations—and the commitment they entitle-- have been relatively ineffective when major threats to conservation have arisen. In early 2000, a private developer began the construction of a dirt road through the wetland in order to reach the beaches of San San, Soropta and Boca del Drago and promote tourism development. Fundación PA.NA.MA. warned the National Environmental Authority (ANAM) and the Panama´s Civil Society Initiative for the Environment (ISCA) about the impact of this 1.2 km, 5-meter wide road particularly on the water flow within the wetland, the destruction of vegetation and the long-term effects. Later on Fundación PA.NA.MA., Grupo de Humedales y Zonas Costero-Marinas de Panamá (supported by UICN), ISCA, Círculo de Estudios Científicos Aplicados (CECA), Asociación Oceánica de Panamá and Fundación para la Protección del Mar (PROMAR) encouraged ANAM to stop road construction. ANAM imposed a fine and stopped the construction. However must of the infrastructure had been built by then.
ANAM and GEF´s Mesoamerican Biological Corridor of Panama´s Atlantic Coast project conducted an environmental impact study confirming the menace this road entitles for the wetland long-term survival and the need of removing what has been built. The road remains the wetlands most important threat as it is blocking and changing the natural waterflow and forest composition. More recently, the Office of the Ramsar Convention has demanded from ANAM the inmediate removal of the road. The current situation shows how little patrolling and monitoring is being conducted by ANAM, given its strong limitations in personnel and equipment, and how dire the need is for further protection measures.
The possibility of developing energy generation projects still keeps a high profile. The Changuinola and its tributary the Teribe have the greatest hydroelectric potential of any rivers in Panama. Six potential sites have been identified for dams and some require the diversion of the waters of the Río Changuinola to the Bahía de Almirante. The Teribe would be diverted into the San San, increasing its volume by an additional 39 cubic m/sec thus potentially adversely affecting the sites natural composition. In 1999, the Panamanian government granted a concession to Hidroecologica del Teribe S.A. (HEC) to develop a 30 megawatt, run-of-the-river hydroelectric power plant and a reservoir at Quebrada Bonyic, the Teribe´s main source. In 2004, HEC, a Colombian public utility company called Empresas Públicas de Medellín (EEPPM), Administradora ServiAgro, Consultores Associados de Ingenieria S.A. and MacEnergy (Cayman) Limited were granted permission to conduct this hidroelectric power project. Project costs have been estimated at 50 million USdollars and this consortium has asked the Interamerican Development Bank (IDB) for a 35 million-dollar grant. Though very few activities have started, the project has sparked internal conflicts among the Naso Teribe indigenous people--who live along the banks of the Teribe and have claimed the government to give their lands an indigenous territory status. More power generation concessions for this area have been requested to the government.
A peat deposit---measuring 82 sq km with an average thickness of 8 m and containing 72,160,000 metric tons- is located between Almirante and Boca del Drago has been proposed for exploitation to provide fuel for local generation of electricity. Given Panama´s growing dependence on fuel to provide energy and the fact that no fuel deposits have been found, the government has focused on promoting hidro-electric power generation and the use of other local energy sources, including peat, still looms in the future.
The local population has become aware of environmental considerations that directly pertain to manatee conservation. Probably such awareness is a product of the local´s concern on safety of water supply, the effect on humans of exposure to chemicals in the banana industry and also environmental education and health programs. Organized around the Asociación de Amigos y Vecinos de la Costa y la Naturaleza (AAMVECONA), the local community has often led conservation efforts in the area. AAMVECONA obtained support from ANAM and GEF´s Mesoamerican Biological Corridor of Panama´s Atlantic Coast to undertake environmentally sound economic activities and overcome their dependence on subsistence agriculture and sea turtle hunting and egg collection.They built a community development center that also serves as ecotourism center and may be used as a field base facility by researchers. In recent times, the organization has conducted monitoring activities along with ANAM personnel, particularly to protect manatees and sea turtles. It also organizes nature tours to the wetlands, an activity that brings large numbers of eco-tourists and has become a successful income generating activity.
Using the manatee as its flagship species, AAMVECONA recently obtained support from Conservation International´s Critical Ecosystem Partnership Fund (CEPF) to conduct an initiative called Raising Awareness to Conserve Manatee Habitats (Trichechus manatus) through Environmental Monitoring in Local Communities. The grant will fund water quality analysis to identify pollutants and their sources, placement of signs in priority sites for manatees and a public education campaign to increase awareness of manatee protection. Fundación PA.NA.MA. has established a partnership with AAMVECONA, ANAM and the University of Panama, as there is a keen interest on integrating each organizations´ different but complementary activities on manatee conservation.
Part III: Conclusion
Despite the lesser number of overflights and the shorter span of time during research, the data collected indicates that the number of manatees sighted surpasses that of the 1987 survey. Though tagging and tracking on individuals will be required in the near future to ascertain this analysis---and to attempt to establish migration patterns, or manatee´s movement between or isolation within river systems—it seems the manatee stock living in the closeby riverine and coastal areas between the Sixaola, San San and Changuinola rivers is succesfully breeding and increasing.
Areas in Bocas del Toro where sightings were repeatedly made on replicate surveys were centered around large rivers and associated lagoons where very little human settlement exists. In Panama manatees seem to rely heavily on true grasses and freshwater macrophytes for food. Sightings in marine habitats were rare. Occasional illegal hunting may still occur, but did not seem to be widespread. Importantly, regulations intended for management of fisheries prohibit gill-netting in these rivers, and the incidental take of manatees in nets commonly noted in other countries was not reported. This may be a key to the persistence of the small surviving population of manatees in Bocas del Toro Province.
The number of threats for the manatees survival has increased in the last 20 years. Traditional threats have significantly diminished while modern forms of environmental degradation continue impacting the manatees habitat. Proposed development projects do pose the greatest danger for the long-term survival of manatees. However these projects have found strong resistance and objections from local organizations, environmental NGO´s and international environmental agreements and conventions who have been successful in preventing further damage.
The local inhabitants´ experience with environmental degradation and their access to environmental education have provided the ground for the establishment of local conservationist and sustainable development organizations, namely AAMVECONA. These organizations have become important actor in manatee conservation and their participation is key in securing long-term protection. It is expected they will become its main protagonists.
Habitat utilized there is mostly undeveloped, but large increases in settlement are likely soon. Conservation plans limiting development and hunting along lower reaches of rivers in Bocas del Toro, and continued enforcement of net regulations, might allow this population to provide the nucleus for future recolonization of other suitable habitat in Panama and adjacent countries.
Part IV: Current Needs and Future Activities
1. Different from neigboring countries Costa Rica and Colombia, there is no official plan or strategy to conserve manatees and their habitat in Panama. The current survey will be an instrumental tool to encourage ANAM and other local actors to develop that plan.
2. In the coming months, the survey will continue at the Manantí, Guariviara, Dayra, Cricamola, Cañaveral and Begae rivers, and the Jugli and Damani lagoons; potentially, further research could continue in suitable habitat between the Calovébora and Miguel de la Borda rivers and at the Panama Canal´s Gatún Lake in order to cover the entire local manatee range.
3. Once the survey has been concluded in the entire local manatee range, Fundación PA.NA.MA. will be ready to start a manatee tracking project in order to know the movements and routes used by manatees.
Part IV: Funding and Collaboration
Funding for this early part of research in Panama´s manatee habitat came from a generous grant from The Van Tienhoven Foundation for Nature Protection. Lighthawk Foundation—a US-based foundation that donates flying time throught its pilot corps- was an important collaborator as it provided a pilot (Kevin Roache) and a co-pilot Elizabeth McDonald who bravely undertook the flights despite rough and rapidly changing weather conditions in the research area. The project received expert advise from Ellen Hines (PhD), Assistant Professor at the Department of Geography & Human Environmental Studies of San Francisco State University, and Caryn Self Sullivan (MSc)), from Texas A&M University,President & Co-Founder of Sirenian International Inc., who have extensive experience in manatee research in Belize´s keys and atolls. Funding to continue this survey was recently granted by The Rufford Foundation for Nature Conservation.
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1 Manatees are mature and able to breed at about 10 years of age. The gestation period is one full year for manatees, and cows give birth only once every 3 to 5 years.
2 UNEP (UN Environmental Program) – SPAW (Convention for the Protection and Development of the Marine Environment of the Wider Caribbean Region). The plan is mostly based upon scientific data from the 1970´s and 80´s as well as short manuscripts on the general condition of local populations.
3 Throughout late 2004 and early 2005, the area has been subject to heavy rainfall and cloudy skies and three major floods have heavily impacted local infrastructure and livelihoods prompting the government to declare it an emergency area. The turbid but usually slow moving waterways--manatee habitat- have often become the main discharge channels. Under these conditions, overflights had to be conducted in exceptionally sunny days with clear skies.
4 The lower Sixaola river marks the boundary between Panama and Costa Rica, thus manatee populations found in this river might be wrongly accounted as separate populations.
X Different from the classic images of Floridian waterways, the waters, rivers, lagoons and channels in the research area are extremely turbid and murky making observation quite a challenge.
5 The project has received expert advise from Ellen Hines (PhD), Assistant Professor at the Department of Geography & Human Environmental Studies of San Francisco State University, and Caryn Self Sullivan (MSc)), Department of Wildlife and Fisheries Sciences, Texas A&M University, who have extensive experience in manatee research in Belize´s keys and atolls.