Lecture 3: Pollution and Disease

Lecture 6: Pollution and Disease in the Marine EnvironmentPollutants in the OceanSewageStormwater runoffOil/petroleum productsIndustrial pollutants & metals (includes mercury and lead)Persistent Organic Pollutants (POPs)Dumping (of dredge materials and trash)Nutrients

SewageNutrientsFecal coliforms, fecal Streptococci, & enterococcus bacteriaPharmaceuticals (estrogens, antidepressants), caffeineSuspended particulate matter (increases turbidity)

www.seaweb.org

Stormwater RunoffSedimentsTrashNutrientsOilPesticidesHerbicidesSewageAnimal waste

Pinellascounty.org

Modmobilian.comOil/Petroleum PollutionLarge scale oil spills (Deepwater Horizon, Torrey Canyon, Exxon Valdez)Small scale spills (spills at oil terminals, groundings of small vessels, routine release of oil from offshore drilling activities)Vessel operations (illegal tank cleanouts, discharges)Municipal and industrial effluentsNatural seeps

whoi.edu

Oil/Petroleum Pollution

Trash

Threats to WildlifeSwallowing plastic debrisEntanglement

Persistent Organic Pollutants (POPs)POP = a substance that possess toxic property and resists degradationExamples: DDT, lindane, PCBs, dioxinsStored in the fatty tissue and organs of animalsCan disrupt endocrine system, case cancer or genetic defects, weaken immune systems

sustainable-nano.com

www.worldoceanreview.com

MetalsDo not decompose under normal environmental conditions and can accumulate in the environment and in living tissues

Mercury contamination in the sea

Nutrient Enrichment/Eutrophication

Effects of EutrophicationAlgal overgrowth of marine ecosystemsHypoxia and formation of dead zonesStimulation of HABs

Disease in the Marine EnvironmentAffects organisms ranging from coralline algae to manateesInfectious diseases are transmitted by pathogensLack Information on disease processesDynamics of host population regulationFactors that promote disease emergence and outbreakMechanisms of pathogen transmissionCauses of DiseaseVirusesAre the most abundant plankton in the seaHosts include bacterioplankton and phytoplanktonHave a significant impact on primary production in the seaFungiSlime moldsBacteriaProtozoansHABs

Effects of DiseaseChanges in community structure

Catastrophic population declines

Seaotters.com

Is Disease on the Rise?Ex. GTFP (green turtle fibropapillomas)

www.turtles.org

Role of Climate Change and Humans in Marine DiseasesTwo ways climate change and humans can increase the occurrence of marine diseaseIncrease the rate of contact between novel pathogens and susceptible hostsExamples: Transmission of canine distemper virus from sled dogs in Antarctica to crab-eater seals; harbor seals infected with influenza virus A (New England) and influenza virus B (Netherlands)Altering the environment in favor of the pathogenExamples: Spread of Dermo from warm southern waters to warming waters along Atlantic coast; corals have increased susceptibility to an infectious cyanobacteria during warm water associated bleaching events; polluted habitats increase organisms susceptibility to disease

Disease and BiodiversitySometimes disease outbreaks can increase biodiversity (Ex. Sea urchins in kelp forests; crown-of-thorns starfish on coral reefs)Is growing concern that the increase in the frequency and impact of disease outbreaks will negatively affect biodiversity, but hard to predict extent of effectsDisease-mediated extinction is likely to be rareMarine Disease Research PrioritiesLong-term monitoring

Better understanding of disease dynamics

Consideration of diseases in marine reservesOyster DiseaseDermo (protozoan parasite, Perkinsus marinus); MSX haplosporid multinucleated sphere, Haplosporidium nelsoni)

Dermo arrived early in the Chesapeake, but its effect in Maryland wasn't fully felt until years after MSX hit, when drought caused both diseases, which thrive in higher salinities, to spread. Together, these diseases decimated what was once the Chesapeake's most valuable fishery. Source: Graph, NOAA Fisheries Annual Commercial Landings Statistics Database28Coral Disease

Photographs of the following diseases are shown: bleaching of Oculina patagonica (a); Aspergillosis of Gorgonia ventalina (b); white band disease of Acropora cervicornis (c); white plague disease of Diploria strigosa (d); white plague disease of Favia favius (e); white pox disease of Acropora palmata (f); yellow blotch disease of Montastraea faveolata (g); and black band disease of Diploria strigosa (h). We thank L. Richardson and NOAA for photographs bd and fh.29Coral Disease

Seagrass DiseaseWasting disease (marine slime mold-like protist Labyrinthula zosterae) Responsible for catastrophic (90%) loss of eelgrass along Atlantic coasts of North America and Europe in 1930s.

Zostera marinaNOAA

responsible for the disappearance of 90% of eelgrass in the 1930's along the Atlantic coasts of North America and Europe (Muehlstein, 1989). Though Z. marina has made a moderate return since then, the disease still affects eelgrass beds in North America and Europe and has been deemed responsible for some recent losses, though none as catastrophic as the epidemic of the 1930s (Short et al., 1986, 1988, 1993a; den Hartog, 1994). 31