Role of marine and freshwater aquatic protected areas: pros and - PowerPoint PPT Presentation

Role of marine and freshwater aquatic protected areas: pros and cons Steve Healy, Roger Chen, Mike Brassard CONS 486 Feb 27 th , 2015

Overview • Introduction to Marine Protected Areas (MPAs) • Paper review • Pros and cons of MPAs • Discussion Questions Mediterranean.panda.org

Definition Marine protected areas can be defined as ‘‘Any area of intertidal or subtidal terrain, together with its overlying water and associated flora, fauna, historical and cultural features, which has been reserved by law or other effective means to protect part or all of the enclosed environment’’ (Kelleher and Kenchington, 1992) A clearly defined geographical space, recognized, dedicated and managed, through legal or other effective means, to achieve the long-term conservation of nature with associated ecosystem services and cultural values. IUCN

Categories • Strict Nature Reserve • Wilderness Area • National Park • Natural Monument or Feature • Habitat/Species Management Area • Protected Landscape/ Seascape • Protected area with sustainable use of natural resources Image: noaa.gov IUCN Commission on National Parks and Protected Areas

Categories US government categorizes MPAs according to conservation focus and level of protection: Conservation focus: • Natural heritage • Cultural heritage • Sustainable production Image: noaa.gov

Categories US government categorizes MPAs according to conservation focus and level of protection: Level of protection: • Uniform multiple-use • Zoned multiple-use • Zoned multiple-use with no-take area • No-take • No-impact • No-access Image: noaa.gov

Examples Biggest MPA in the world: • The Papahānaumokuākea Marine National Monument • In the middle of pacific ocean near Hawaii • 362,072 km 2 • Over 7,000 marine species • Home to many rare and endangered species such as the green sea turtle and the Hawaiian monk seal. Images: noaa.gov

Examples The Bowie Seamount Marine Protected Area: • The Bowie is the shallowest seamount in Canada's Pacific waters and one of Earth's most biologically rich submarine volcanoes. • Situated about 180 kilometers offshore of Haida Gwaii Image: DFO

Examples (Freshwater) Great Lakes : • Have 10800 km2 protected area • Reduce non-native sea lamprey (Petomyzoa marinus) in the North American Great Lakes, • Combined with reduced fishing pressure, has allowed native lake trout (Salvelinus namaycush) and whitefish (Coregonus clupeaformis) populations to rebound Image: DFO

Examples (Freshwater) Lake Superior National Marine Conservation Area , Ontario : • The world's largest freshwater protected area with a surface area of over 10 000 km 2 • It covers about one third of the Canadian portion of Lake Superior and extends to the Canada-United States border.

Functions and impacts Protect and conserve: • Commercial and non-commercial Fishery resources and their habitats; • Endangered marine species and their habitats; • Unique habitats; • Marine areas of high biodiversity or Biological productivity; and • Any other marine resource or habitat necessary to fulfill the Minister’s mandate . -- DFO

Paper Overview and Critique www.sayleeseafood.com

Great Scallop ( Pecten maximus ) • Marine bivalve mollusc • Inequivalve - Right/lower shell is convex - Left/upper is flat • Typically 10-15 cm in length - Recorded sizes up to 24 cm FAO.org • Sand, gravel, and mud bottoms - Range from intertidal to 250 m • Attached to substrate when young - Free swimming as adults • Filter feeders - Most active during day Paul Naylor

Global Capture of Pecten maximus

Aims of study “The specific aims of the study were to test for differences in the abundance, body size, and allocation of tissue mass to gonads or soma in scallops sampled in areas subjected to different regimes of fishing activity.” - Kaiser et al. 2000

Hypothesis • Areas open to commercial scallop fishing activity expected to have on average: 1. Lower abundance 2. Smaller scallops And  the release of competition for resources might lead to larger somatic growth and investment in reproductive tissues.

Design • Inshore Potting Agreement (IPA) - area of ~500km 2 - established for over 25 yrs - voluntary participation until 2002 - excludes the use of towed bottom- fishing gear • 3 fishing regimes tested: – Fished sites open to scallop dredging year round or fished illegally on annual basis (1,2,3,4,5) – Ex-fished sites illegally scallop dredged 18 months previously but not before this period (6,7) – No-fishing sites never subjected to towed bottom-fishing gear (8,9)

Scallop Dredging - Process scotland.gov.uk lookforthehook.wordpress.com

Methods • 3 replicate tows per site – 10 minute bottom-time durations • Minimum landing size of 10cm shell height • Habitat similar across all sites – Coarse gravel, sand, and mud • 4 dredges used per tow http://www.gulfofmaine-census.org/education

Methods • Annual rings on shell used to determine age of individuals • Gonads and adductor muscle dissected out, dried, and weighed – Gonads  larger = greater reproductive success (broadcast-spawners) – Adductor muscle is main mechanism of protection from most common predators (Common starfish) • Damage scars counted on right-hand valve – Any irregular indentations on edge of shell or previously repaired injuries flickrhivemind.net forestryimages.org

Methods Adductor muscle Wikipedia Commons Gonad

Results • Mean abundance of scallops was highest in no-fishing areas – 12.8 times higher abundance than fished sites – Lowest in fished areas immediately surrounding the IPA • Scallops sampled from no-fishing areas had highest mean ratio of gonad dry weight to adductor muscle dry weight – 19% and 24% compared to fished and ex-fished sites respectively • Scallops collected in ex-fished areas were smaller in size and abundance – Short but intense period of selectivity for large individuals • Fished sites also showed higher incidence of shell scars due to injury – Due to inefficiency of dredging

Discussion • An estimated 15.9 times greater reproductive potential in scallops sampled from protected areas compared to fished sites - Larger gonads believed to increase reproductive potential - Broadcast spawning means reproductive success is highly density dependent - Energy expended repairing injuries lowers reproductive potential

Criticisms • Small # of sites sampled – Permission needed from fishers with static gear in plots (legal fishing) • Information on historical use of fishing grounds provided by fishers and govt. – Nothing to gain or lose by lying? – 10 yr working relationship • Scallop abundance varied significantly among replicate sample sites – Few replicates and little consistency in site history • Not certain whether reduced gonad size resulted in fewer or smaller eggs – Smaller egg size directly effects egg survival (Martinez & Perez 2003)

Positive Aspects • Comparison of observations to other, larger surveys – NE coast of USA (Murawski et al. 2000) • X 14 increase in biomass within MPAs – Isle of Man, UK (Beukers-Stewart et al. 2005) • X 11 increase in biomass within MPAs • Observation of injuries caused by fishing equipment – Effects on allocation of individual’s resources (repair vs reproduction) – Chronic fishing and associated injuries lower reproductive potential • Repeated suspension of sediments caused by bottom fishing and effects on food supply • Reproduction through broadcast spawning – Density dependency

In summary… “It would appear that areas protected from the effects of bottom fishing not only conserve population abundance and biomass of bivalve molluscs, but also maintain reproductive quality, which is greatly reduced in areas exposed to chronic fishing.” - Kaiser et al. 2000

Pros and Cons Of Marine Protected Areas Photo: Wikimedia Commons

Ecology - Pros A 2009 Meta-analysis study of Marine Protected areas (MPAs) worldwide: • Data from 124 fully no-take reserves • Improvements in biomass, density, size and species richness • Huge variation! (site-specific differences, or activities outside MPAs?) (Lester et al., 2009)

Ecology - Cons • Of 1306 MPAs studied, only 31% were meeting conservation goals (Kelleher et al., 1995) • Not all species respond equally to MPAs (Lester et al., 2009) %

Socio-economic - Pros • MPAs for tourism = good for economy! (Brown et al., 2001)  eg. diving opportunities on coral reefs  positive feedback: tourism encourages further conservation of corals (Brown et al., 2001) • Can create jobs for locals (Brown et al., 2001)  management, monitoring www.donquijote.org www.isvolunteers.org

Socio-economic - Cons • Can put fishers in area out of work (Brown et al., 2001) • and/or push locals out of area entirely Flickr.com • Development of tourism near MPAs can cause increases in non-point sources of pollution! (Brown et al., 2001)  (eg. urban runoff, eutrophication) • MPAs are expensive to implement, manage and monitor (White, 2002)

Socio- economic + Ecological (it’s complex!) Low development, Low development, High development, High development, Low management High management Low management High management (Brown et al., 2001)