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Introductory Lecture SIO 296 January 7, 2010 • Ocean Commons – Where and what it is – Relevant policy instruments • Spatial structure – Why it is important – How it is studied Ocean Commons • What is the Ocean Commons? • A place • A concept Boundaries? Land May Have More Definitive Boundaries These may confine a species Physical Characteristics that Divide the Sea • • • • Currents Light availability Nutrients, food Bottom characteristics •Organisms such as sea turtles and birds also utilize terrestrial habitats and so land characteristics might also affect distribution. Political boundaries On land might be a town, city, Economic state, country Exclusive Zone 200 nm www.mcatoolkit.org High Seas Defines the Ocean Commons Seaaroundus.org Not part of EEZ; 64% of the world’s oceans Marine Resources Move blue=bluefin; green=leatherback; pink=petrel blue=salmon shark; green=leatherback; pink=shearwater From Meltzer Instruments for Management? International Treaties & Agreements • United Nations Convention on the Law of the Sea (UNCLOS) • Convention on Migratory Species (CMS) • Convention on International Trade in Endangered Species (CITES) • Straddling Stocks Agreement: RFMO’s Intergovernmental Organizations Birdlife.org Regional Fisheries Management Organization (RFMOs); http://www.fao.org/fishery/rfb/search/en Bilateral Agreements • When just two countries are involved: Kemp’s Ridley US-Mexico example in Dutton & Squires 2008. • Dutton & Squires 2008: Binding v. nonbinding agreements; carrots and sticks. The Ocean Commons • A concept: The ocean as a shared resource especially when it comes to highly migratory organisms. • A place: The High Seas (beyond the 200nm EEZ) where property rights may be ill defined. • The organisms we’ll consider in this section are managed by many nations and are part of the Ocean Commons. Photo: Scott R. Benson, NMFS Southwest Fisheries Science Center Noaa.gov Noaa.gov Highly Migratory Species • Term derived from the United Nations Convention on the Law of the Sea – wide geographic distribution – both inside and outside EEZ – undertake migrations across oceans – pelagic species (but may spend part of their life cycle in nearshore waters). – harvested by U.S. and foreign fishing fleets. Species managed in the Pacific • Tunas: north Pacific albacore, yellowfin, bigeye, skipjack, and northern bluefin • Sharks: common thresher, pelagic thresher, bigeye thresher, shortfin mako, blue • Billfish/swordfish: striped marlin, Pacific swordfish • Dorado (dolphinfish, mahi-mahi) • http://www.pcouncil.org/hms/hmsback.html Spatial Structure • Why is spatial structure important? • What factors shape spatial structure? – Physical boundaries (currents, landmasses, bottom topography). – Biological requirements (food, habitat; this may change over the life of the organism). Types of Movements • Short term (vertical) •Importance? -Fisheries interactions -Predictions Types of movement • Short term (vertical) – Foraging – Holding (fishes) • Conservation relevance – Fisheries interactions – Protected areas (habitat-use) • Predictive utility Godley et al.: 2007 Unit of management • Protecting the genetic diversity and evolutionary potential within a species: – subspecies – population – management units – distinct population segments • Adaptation to a changing environment. • Homing fidelity; breeding ground distinctions. Scale • Geographic • Political • Evolutionary • Tools Tagging • Affixing a mark (internal or external) so an animal can be recognized. • Spotila et al. 2000, Dutton et al. 2005: tagging with PIT tags and monitoring returns. • Movement; Mark-recapture methods to estimate abundance. • Wide-scale monitoring often needed. EFFORT INTENSIVE Acoustic tags • Pingers (acoustic or sonic tags) emit a sound in a unique code that allows identification of an animal. • Stationary or mobile receiver. • Coastal arrays inform long-distance movement • Small-scale movements; no recapture. Lindley et al. 2008 green sturgeon migration using sonic telemetry: •Tagged in spawning and summer aggregation areas. •Migrated to feeding areas in Canada in fall and back down in spring. •Aggregate in an area in Canada that has bottom trawl fishing (includes individuals protected under US ESA protection). Limitations? • Only detected if there is a receiver. • Multiple individuals need to be tagged to make general conclusions; variation exists in movement behavior. Satellite Tags • Provide information without re-capturing. Collected Information is transmitted via satellite. • Satellite tags transmit when animal is above the surface of the water for a period of time. • Tag type depends on animal behavior (does it surface often). Marine Resources Move blue=bluefin; green=leatherback; pink=petrel blue=salmon shark; green=leatherback; pink=shearwater Figure 1. Positions of Atlantic bluefin tuna at three western Atlantic locations (arrows) during 1996–2004. Circles represent daily locations. a) Fish classified as western breeders – 36 fish; b) Fish classified as eastern breeders – 26 fish; c) Fish that did not visit a known breeding ground – 268 fish. Triangles represent locations where tagged fish were caught by fishermen. The dashed line indicates the current management boundary (45ºW meridian). http://tagagiant.org/Summary_Nature.shtml Genetics • Define population structure, identity of units below the level of the species. • Prioritize conservation areas (breeding congregations). • Attribute origin to individuals at a foraging ground; mixed stock analysis. http://tagagiant.org/Summary_Nature.shtml Summary Points • The Ocean Commons (resources and place) can be studied and managed using scientific and policy tools; tools and scale are applicable outside of the commons. • Understanding spatial structure is vital to good management. • Sea turtles as a case study: Move across high seas, encounter fisheries in and out of EEZ, benefit from place-based conservation.