Wijngaarden, R. van

Saliña Goto and reduced flamingo abundance since 2010 Ecological and ecotoxicological research

In 2010 a petrochemical fire took place at the BOPEC oil terminals on Bonaire. These facilities are located on the shores of the Goto lake, a legally protected RAMSAR wetland and important flamingo foraging area. Before the fire, daily flamingo counts averaged approximately 400 birds that used the area to feed on Artemia (brine shrimp) and Ephydra (brine fly larvae). Immediately after the fire, flamingo densities plummeted to nearly none and have not recovered. A large amount of fire retardants were used to combat the fire, and were hypothesised to be a potential cause for the flamingo declines. Our analyses of 15 years of baseline flamingo monitoring data show that rainfall does influence flamingo densities but only on the short-term and steering seasonal dynamics of flamingos. Therefore the rainfall event/change in the rainfall regime cannot account for lasting absence of flamingos. Nearby control lakes that were not affected by the fire showed no lasting reduction in flamingo densities, but instead an increase due to the birds no longer feeding in Goto.

In 2012, we measured the concentrations of polycyclic aromatic hydrocarbons (PAHs) and perfluorinated compounds (PFCs, which includes PFOS) in Goto and control-lake waters and conducted additional chemical screening (fingerprinting) of sediments and biota. These measurements showed both lasting elevated levels of PFCs, in water, sediments and biota (fish) and lowered food-species concentrations in Goto as compared to control areas. Based on calculated Risk Quotients combined with the chronic exposure, for the documented PFOS levels, toxicological effects on benthic organisms such as Artemia and Ephydra are likely. Nevertheless additional impact by other associated retardant toxicant is also probable. Goto was found to be chemically different based on GC*GC chemical fingerprinting indicative of elevated Butylated Hydroxytoluene (BHT) concentrations, a compound used in petrochemical industries as a solvent.

In conclusion, our results demonstrate a close link between the 2010 Bopec fires and the subsequent abandonment of the adjacent Goto lake by foraging flamingos. Compared to nearby control lakes, Goto was found to have elevated (and toxic) concentrations of PFCs and associated low food species concentrations. Therefore, our results suggest that the lasting abandonment of the lake by flamingos after the fire have been due to the drastically low food-species densities as likely caused by toxic ecosystem effects resulting from retardants released into the environment while combatting the fires. 

Date
2013
Data type
Research report
Theme
Research and monitoring
Report number
C211/13
Geographic location
Bonaire

Saliña Goto and reduced flamingo abundance since 2010 - Ecological and ecotoxicological research

Abstract:

In 2010 a petrochemical fire took place at the BOPEC oil terminals on Bonaire. These facilities are located on the shores of the Goto lake, a legally protected RAMSAR wetland and important flamingo foraging area. Before the fire, daily flamingo counts averaged approximately 400 birds that used the area to feed on Artemia (brine shrimp) and Ephydra (brine fly larvae). Immediately after the fire, flamingo densities plummeted to nearly none and have not recovered. A large amount of fire retardants were used to combat the fire, and were hypothesised to be a potential cause for the flamingo declines. Our analyses of 15 years of baseline flamingo monitoring data show that rainfall does influence flamingo densities but only on the short-term and steering seasonal dynamics of flamingos. Therefore the rainfall event/change in the rainfall regime cannot account for lasting absence of flamingos. Nearby control lakes that were not affected by the fire showed no lasting reduction in flamingo densities, but instead an increase due to the birds no longer feeding in Goto.

In 2012, we measured the concentrations of polycyclic aromatic hydrocarbons (PAHs) and perfluorinated compounds (PFCs, which includes PFOS) in Goto and control-lake waters and conducted additional chemical screening (fingerprinting) of sediments and biota. These measurements showed both lasting elevated levels of PFCs, in water, sediments and biota (fish) and lowered food-species concentrations in Goto as compared to control areas. Based on calculated Risk Quotients combined with the chronic exposure, for the documented PFOS levels, toxicological effects on benthic organisms such as Artemia and Ephydra are likely. Nevertheless additional impact by other associated retardant toxicant is also probable. Goto was found to be chemically different based on GC*GC chemical fingerprinting indicative of elevated Butylated Hydroxytoluene (BHT) concentrations, a compound used in petrochemical industries as a solvent.

In conclusion, our results demonstrate a close link between the 2010 Bopec fires and the subsequent abandonment of the adjacent Goto lake by foraging flamingos. Compared to nearby control lakes, Goto was found to have elevated (and toxic) concentrations of PFCs and associated low food species concentrations. Therefore, our results suggest that the lasting abandonment of the lake by flamingos after the fire have been due to the drastically low food-species densities as likely caused by toxic ecosystem effects resulting from retardants released into the environment while combatting the fires. 

Date
2013
Data type
Research report
Theme
Research and monitoring
Report number
C211/13
Geographic location
Bonaire