| Variable Type | Ordinal |
|---|---|
| Variable Component Type | Environmental Common |
| Variable Kind | Component |
| Theme | Spatial (learn about themes) |
| Projects | SESMAD, Fiji fisheries |
| Question | The extent to which the distribution of the environmental commons is highly uneven across space. Analogous to resource “patchiness” for natural resources. Low heterogeneity means that a resource is continuously distributed. |
| Select Options | 1 Low, 2 Moderate, 3 High |
| Unit | |
| Role | |
| Importance | "The distribution of a commons in a landscape may influence the costs associated with harvesting, managing, monitoring and collecting information about resource conditions. In general we expect patchy distributions to increase the costs associated with these activities, and reduce the incentives to manage a commons. Additionally, high heterogeneity may cause problems with localized pollution ""hot spots"" or localized resource degradation." |
| Definition | "The distribution of a commons in a geographic area along a scale from uniform (low) to patchy (high) (Bakus 2007). High: Multiple clearly defined sub-units can be identified within the commons Low: No patches or uniform distribution of a commons over its spatial extent." |
| Sectors |
Theory Usages
| Theory | Value Used |
|---|---|
| Cap-and-trade policies | Low |
Associated Studies
| Study Citation |
|---|
Bakus, Gerald J. 2007. Quantitative Analysis of Marine Biological Communities: Field Biology and Environment. John Wiley & Sons. |
Component Usages
| Component | Value Used | Explanation |
|---|---|---|
| Tigris watershed | ||
| Western Atlantic Bluefin Tuna | High (3) | Adult Western Atlantic Bluefin tuna congregate in the Gulf of Mexico during the spawning season. However, for the rest of the year they are distributed widely throughout the Western Atlantic. |
| Walt's forest | ||
| NWHI Lobster Fishery | Moderate (2) | Dispersed throughout area of the NWHI in varying densities due to sexual maturity, spawning seasons, and external climate factors. |
| Macquarie Island Royal Penguin | Moderate (2) | During the breeding season the entire population of Royal penguins is concentrated in and around Macquarie Island; however they are more widely dispersed and patchy during the polar winter. |
| Light Mantled Albatross | High (3) | High site fidelity to breeding site (low heterogeneity); but for much of life cycle are distributed widely. |
| Wakatobi coral cover | High (3) | Corals cluster together in reefs, in a patchwork of reef and non-reef areas. |
| Wakatobi Green Turtle | Moderate (2) | Distributed in tropical and sub-tropical waters. Movements within the marine environment less well understood, but known to use a wide range of broadly separated localities and habitats during their lifetimes. But considered moderate as females return to same nesting beaches. |
| Wakatobi fish spawning | Low (1) | Fish come together to spawn so have low spatial heterogeneity when breeding. |
| Galapagos Green Turtle | Moderate (2) | Green turtles use many locations and habitats which may be quite distant from one another, however females often return to the same nesting beach. The most important nesting beaches in the Galapagos Archipelago are Quinta Playa and Bahía Barahona in Isabela Island, Las Bachas in Santa Cruz Island, Las Salinas in Seymour Island and Espumilla in Santiago Island (Zarate et al 2003) |
| NWHI Trophic Density | Moderate (2) | |
| Salmon | ||
| Raja Ampat Reef Fish | Moderate (2) | Distributed around all parts of the MPA in varying degrees |
| Raja Ampat Coral Cover | Low (1) | Corals cluster together in reefs, in a patchwork of reef and non-reef areas. |
| Galapagos Sharks | Moderate (2) | Many species of shark found throughout the GMR. Some are found more commonly in certain regions, however presence of any one sharks species is unpredictable. Most common species hammerhead and the Galapagos sharks. (Hearn et al., 2013) |
| Raja Ampat Green Turtle | Moderate (2) | Distributed in the sense that they migrate all over the indo-pacific ocean but return to the same nesting beach each year. The nesting locations in the Raja Ampat area are Wayag-Sayang, Ayau-Asia, Kofiau, Boo Isles, and Southeast Misool. |
| NWHI Green Turtle | Moderate (2) | Distributed in tropical and sub-tropical waters. Movements within the marine environment less well understood, but known to use a wide range of broadly separated localities and habitats during their lifetimes. But considered moderate as females return to same nesting beaches. |
| California Rocky Shores Ecosystem Health | High (3) | Rocky shores are broken up by natural patches such as natural beaches and cliffs, while manmade structures have broken up the rocky shoreline. Rocky shores are connected by the California current, providing a sort of fast highway to connect the various strips of rocky shores. Within the ecosystem, rocky shores are well known to be very patchy and to respond in succession to events (Paine and Levin 1981; Sousa 1984, 1985). |
| California Humpback Whale | High (3) | While migration routes are somewhat known, finding a whale at any one point is not guaranteed and these are vast areas. |
| California Groundfish Habitat | Moderate (2) | The Essential Fish Habitat map shows that the southern end of the sanctuaries is quite patchy, while there are larger areas for ESH toward the north. Kelp forests, rocky reefs, and sea grasses can also be quite patchy. |
| Svalbard Polar Bear | Moderate (2) | Moderate Polar bears are found throughout the polar regions near land with seasonal sea-ice (Mauritzen et al 2002), but are found on some islands in much higher density (e.g. Kong Karls Land). |
| Seaflower coral reefs | Missing | NO DATA |
| Seaflower groupers | Moderate (2) | Groupers are associated with coral reefs although they are mobile. |
| Svalbard Beluga | Moderate (2) | Modern vessels have greatly increased the ability to travel in the oceans around Svalbard, but seasonal sea ice sometimes limits vessel traffic. Technologies such as sonar can make it easier to locate the belugas, but low densities of these whales make sightings relatively uncommon. |
| Community G Fish Resources | Low (1) | |
| Community E Fish Resources | High (3) | |
| Community F Fish Resources | High (3) | |
| Community H Fish Resources | Low (1) | |
| Svalbard Shrimp | Moderate (2) | The distribution density of shrimp is moderately patchy (NAFO 2011). Ares in the southern region of the Nature Reserves have quite low densities of shrimp, while regions in the north and northwest of the Nature Reserves have high densities. |
| GABMP (Commonwealth Waters) Southern Right Whale | Moderate (2) | Southern right whales are a migratory species and the pathways of southern right whales between their main foraging grounds in the Southern Ocean and the calving grounds in the Great Australian Bight region are poorly understood. The movements of males, non-breeding females and sub-adults are less understood than breeding females, which return to the same coastal calving beaches every 3 - 4 years. Finding a southern right whale at any one point during the summer months when whale migration is occurring is not guaranteed. However, female whales and their calves are observed frequently from the cliffs at the Head of Bight in the near shore waters of southern Australian during the winter months. |
| GABMP (Commonwealth Waters) Southern Bluefin Tuna | Moderate (2) | Low Commons Heterogeneity - Sexually mature SBT congregate in a single spawning ground located in the north-east Indian Ocean between Java and Western Australia (Caton, 1991; NSW DPI FSC n.d.; BRS 2008). Spawning occurs from August - April with a peak from October - February (Honda et al. 2010). SBT are highly migratory, however they congregate in a single spawning ground therefore coded as moderate heterogeneity. High Commons Heterogeneity - For the rest of year the tuna are distributed throughout the south-west and south-east Atlantic Ocean, eastern and western Indian Ocean and the south-west Pacific Ocean (Collette et al. 2011). Tuna are suggested to congregate at seamounts, lumps and reefs in the Great Australian Bight where prey species also congregate, and to move depending on water masses, such as influxes of nutrient rich sub-Antarctic waters, and sea temperatures (Fujioka et al. 2010) |
| King Penguin | Moderate (2) | Populations are more concentrated at colonies during the breeding season, but can disperse widely during foraging and when not breeding. |
| Cenderwasih green turtle | Moderate (2) | Distributed in tropical and sub-tropical waters. Movements within the marine environment less well understood, but known to use a wide range of broadly separated localities and habitats during their lifetimes. But considered moderate as females return to same nesting beaches. |
| GABMP (Commonwealth Waters) Sea Lion | Moderate (2) | |
| Svalbard Kittiwake | Moderate (2) | Ranges widely across open sea but returns to the same breeding colonies |
| Cenderwasih target fish | Moderate (2) | Distributed around all parts of the MPA in varying degrees |
| Patagonian squid (Loligo gahi) | Moderate (2) | Within the Loligo Box, there are years where one area has higher reported catches than others. However, the entire box has reported catches, thus the resource is not patchy over a season. However, over a season fish are sometimes found in high numbers in certain areas and none in others. Also Loligo are found outside the box as well. |
| Arrow Squid (Nototodarus spp.) | High (3) | Quite patchy – Smith et al 1987 – different subpopulations – Fig 5 shows just how patchy. |
| California market squid (Loligo opalescens) | High (3) | Very patchy (even referred to as patchy in the management plan). |
| New Zealand Sea Lion | ||
| Coral reefs, coast and small-island on and surrounding Gili Trawangan, Indonesia | Moderate (2) | Many dive sites distributed around the islands, it is a network of patchy reef systems |
| Gulf of Nicoya fisheries | High (3) | |
| Galapagos Sea Cucumber | Moderate (2) | found in shallow coastal waters and distributed around all islands of the archipelago in varying densities. |
| Forests in Indonesia | Low (1) | Forests are fairly continuously distributed throughout Indonesia, although they are systematically cleared in some areas. |
| Eastern Atlantic Bluefin Tuna | High (3) | During the spawning season, sexually mature adults congregate in the Mediterranean Sea. There is some debate whether individual adults spawn annually over every 2-3 years. During the rest of the year, however, tuna are distributed widely over feeding grounds. |
| Ozone | Moderate (2) | There is some variability in the distribution of atmospheric ozone. For instance the ozone hole tends to emerge at the poles due to circulation patterns. |
| Ozone Depleting Substances | Low (1) | for coding purposes can be seen as continuously distributed, although there are regions with more or less accumulation. |
| Rhine Point source pollutants | Low (1) | The continuity of the Rhine's watercourse is not significantly or permanently fragmented by dams. |
| Rhine Non-point source pollutants | Low (1) | The continuity of the Rhine's watercourse is not significantly or permanently fragmented by dams. |
| GBR coral cover | High (3) | Corals cluster together in reefs, in a patchwork of reef and non-reef areas. |
| fish | ||
| GBR target fish | ||
| GBR target fish | Moderate (2) | |
| Patagonian Toothfish | Moderate (2) | Patagonian toothfish have a broad circum-Antarctic distribution, but they appear to have a patchy rather than continuous distribution with distinct and potentially isolated populations. Populations seem to be concentrated around islands (e.g., South Georgia) and banks (e.g., Kerguelen Plateau) with the vast deep areas of the Southern Ocean acting to isolate and restrict these populations (see Collins et al. 2010 and references therein). Macquarie Island Patagonian Toothfish tend to be concentrated in two fishing grounds around Macquarie Island; the Aurora Trough and Macquarie Ridge. None of these fishing grounds are within the Macquarie Island Marine Park. |
| Community D Fish Resources | High (3) | |
| Community A Fish Resources | High (3) | |
| Community C Fish Resources | High (3) | |
| Community B Fish Resources | High (3) | |
| GABMP (Commonwealth Waters) Benthos | Moderate (2) | Similar benthic assemblages are found inside and outside of the BPZ of the GABMP (CW) although a marked shift in species representation was observed between the two surveys (2002, 2006). However, populations of individual species had patchy distributions suggesting that a high proportion of the fauna in and around the BPZ of the GABMP (CW) has not yet been sampled (Ward et al. 2003; Currie et al. 2008) |
| GBR Green Turtle | Moderate (2) | In a summary report, Dobbs (2007) suggests that all of the GBR is potential foraging habitat for Green Turtles. However, some foraging areas are more important than others, and nesting sites show strong patchiness towards multiple key areas (Limpus et al 2003). |
| Cenderwasih coral cover | High (3) | Corals cluster together in reefs, in a patchwork of reef and non-reef areas. |
| test | ||
| Mangrove forest in Bragança, Brazil | Moderate (2) | |
| Lombok aquaculture irrigation canals | High (3) | Head and tail-enders have different degrees of water accessibility in the canal system. |