Humpback Whale ContaminantResearch

Cristiane ElfesFISH 475: Marine Mammalogy

April 11, 2007

Outline

Persistent Organic Pollutants

Marine Mammals and Contaminants

Humpback Whale Research

Persistent Organic Pollutants (POPs)

“Human-made chemicals that remain in theenvironment for long periods of time and have theability to bioaccumulate”

Common Characteristics:• Volatile• Lipophilic• Resistent to Degradation

4 Classes:• DDTs• PCBs• HCHs• PBDEs

Bioaccumulation

Large fish

Toothed whales

DDT

INSECTICIDE used against disease vectors, crop andhousehold pests

First reported in Marine Mammal tissues in 1960s Regulatory status:

Banned in most countries Still used in some developing countries to prevent malaria

Potential Health Effects: Neurotoxic Developmental and reproductive effects Carcinogenicity

PCBs

HEAT RESISTANT OILS used in electrical transformers andcapacitors; also used in plastics, inks and other minorapplications

Regulatory Status: Banned in most countries in the 1970s and 1980s

Potential Health Effects: Estrogenic effects Alteration of thyroid metabolism

HCHs

Two forms: Technical HCH - Insecticide Lindane - Seed Dressing, Medication (Lice, Scabies)

Regulatory Status Technical HCH - banned Lindane- still in use (including US, Canada)

Potential Health Effects- Neurotoxic- Liver and kidney damage- Carcinogenicity- Estrogenic Effects

PBDEs FLAME RETARDANT chemicals used in plastics, electronic

equipment and textiles Three forms: penta-, octa-, deca- BDEs Regulatory status:

Penta- and OctaBDEs banned in Europe California: ban on penta- and octa-BDE beginning in 2008. Washington: proposed ban on penta-, octa- and deca-BDE

Potential Health Effects: Developmental neurotoxicants Influence thyroid metabolism Estrogenic effects

PBDEs continued…

PBDEs detected in sperm whales (Boer et al., 1998)

PBDEs detected in Arctic food chains, including beluga whales,ringed seals and polar bears (Wolkers et al., 2004)

Killer whales in northeastern Pacific show high levels of PCBsand PBDEs (Rayne et al., 2004; Ross, 2005)

PBDE concentrations in ringed seals in the Canadian Arcticincreased an order of magnitude in 20-years (Ikonomou et al.,2002)

Marine Mammals and Contaminants

Susceptibility:

Long lived species

Often top level predators

Female transfer of contaminantburden to calves during gestationand lactation (through placentaand later milk)

Diving physiology increasingsensitivity to toxic substances?

Health Implications

Direct MortalityNo evidence for direct mortality

Reproductive Impairment Experimentally verified in harbor seal (Phoca vitulina) (Reijnders, 1986) Other field studies: some pinniped populations and St. Lawrence

beluga whales

Immune Dysfunction/Disease Observed occurrences of tumors, lesions, chromosomal aberrations Occurrence of disease - morbillivirus (phocine distemper virus)

Cause and Effect Relationships are difficult to establish in wildpopulations!

Contaminant Variation

Age, sex, reproductive statusIncrease with age, differences between male and female,female transfer to offspring

GeographicHigher in proximity to point sources, sink areas

Feeding ecologyVaries with position in food chain, differences in feeding ecology

TemporalIncrease over time, changes in DDT/DDE ratios

Humpback Whales(Megaptera novaeangliae)

Baleen whale

Status: Endangered(ESA), Depleted(MMPA)

Can be individuallyidentified my flukephotographs

Feed on euphausiidsand small schoolingfish

Humpback Whale Migration

Migrate fromwinter breedingareas to summerfeeding areas

High degree ofsite fidelity tofeeding areas

Can serve asbioindicators

References

O’Shea, 1999. Environmental Contaminants and MarineMammals - Biology of Marine Mammals. Editors Reynolds andRommel. Smithsonian Press.

O’Shea and Brownell.1994. Organochlorine and metalcontaminants in baleen whales: A review and evaluation ofconservation implications. Science of the Total Environment154:179-200.