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Focal (Flagship) vertebrates. Figure 10.1 Aldabrachelys gigantea was introduced to an island in Mauritius as a taxon substitute for an extinct giant tortoise that dispersed tree fruits on the island. Focal (Flagship) vertebrates.
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Figure 10.1 Aldabrachelysgigantea was introduced to an island in Mauritius as a taxon substitute for an extinct giant tortoise that dispersed tree fruits on the island
Focal (Flagship) vertebrates • -averting the extinction of species with small or declining populations is another motivation for restoration • Ex. Columbia spotted frog is under consideration for listing by USFWS and the restoration team designed a stream of ponds along the river, which support large populations • Fig. 10.2
Figure 10.2 The spotted frog (Ranaluteiventris), a species that lives in floodplain wetlands, was a focal species of the Provo River restoration project
Reducing effects of fragmentation • -vertebrates move through landscapes in response to fluctuations in food availability, changing nutritional demands, predators, or social interactions • -in some cases individual habitat fragments are too small • Ex. Pronghorn in Wyoming migrate over 300 km between winter and summer ranges and must negotiate fences, roads, oil and gas fields, and natural barriers such as rivers • -restored areas that are larger, provide habitat heterogeneity, and/or encompass multiple ecosystems have the greatest potential for restoration • Ex. Costa Rica tropical forest restoration and insectivorous birds Fig. 10.3
Figure 10.3 Larger tracts of restored forest in Costa Rica provided better foraging opportunities for insectivorous birds than smaller tracts
Reducing effects of fragmentation • Ex. Baghmara Community Forest in Nepal was a restoration project that provided a buffer area around Chitwan National Park and tiger populations have increased • -people killed by tigers has increased seven fold while collecting fodder for livestock kept in paddocks following the restoration Fig. 10.4 • -trying to use radio collars so that people can collect fodder in areas without tigers • -habitat may also be restored to facilitate safe movement through the landscape • Ex. Road crossing features Fig. 10.5 • -restoration of corridors of habitat that connect protected natural areas
Figure 10.4 Restoration of forest buffers around Chitwan National Park ended open grazing and required that villagers collect fodder for livestock
Figure 10.5 This overpass in Banff National Park was constructed to facilitate wildlife movement across the Trans-Canada Highway
Reducing effects of fragmentation • -in rivers, an important restoration consideration is ensuring vertebrates have refuge to escape biotic and abiotic stressors • -side channels or floodplains can provide refuges from high flows in main channels and deep holes as well as ponds along sides may persist during drought. Waterfalls or ponds may keep fish from amphibian nesting sites • Ex. Wood frogs in North Carolina were able to persist over a 13-year study period because the restoration design allowed them to shift breeding sites in response to changing environmental conditions Fig. 10.6
Figure 10.6 Within a complex of restored wetlands in North Carolina, breeding wood frogs curtailed egg-laying following fish invasions and used nearby ponds without fish
Figure 10.7 Sustaining a metapopulation requires more habitat area than sustaining individual populations, a mating pair, or a single individual
Figure 10.8 Eurasian spoonbills (Platalealeucorodia) breed in wetlands in the Skjern River restoration area, but also rely on wetlands in West Africa to overwinter
Figure 10.9 (A) Results of a study of restored eucalyptus forests in Australia. (B) Many birds, such as this fuscous honeyeater,find these forests of little use until they are fully recovered
Figure 10.10 Researchers erect an artificial bird perch to determine if this method can increase seed dispersal by frugivorous birds in a degraded tropical forest in Kalimantan, Indonesia
Curbing Overexploitation • Regulation matters. Inadequate laws or not enough wardens affects species harvested by people. • Ex. Protection of gray wolf by ESA has led to an expansion of their range due to the laws protecting wolves and a reintroduction into Yellowstone National Park Fig. 10.11 • Ex. Marine no-take zones in the Great Barrier Reef Marine Park in 2004 resulted in increases in number and size of bony fish and sharks Fig. 10.12 • Ex. Gulf of Carpentaria has resulted in retrieval of on average 1000 nets/year primarily from Asian countries Fig. 10.13
Figure 10.11 Changes in the distribution of the gray wolf in the United States
Figure 10.12 Gray reef sharks (Carcharhinusamblyrhynchos) increased eightfold in no-take reserves in the Great Barrier Reef Marine Park within a few years of their establishment
Figure 10.13 Probable “Countries of Origin” of stranded nets found along the shores of the Gulf of Carpentaria (Australia) as identified by the WWF Net Kit (see Figure 5.5)
Figure 10.14 Removal of forage fish is one of the most commonly used methods for inland lake restorations in Denmark and elsewhere
Controlling Introduced Vertebrates • Eradication
Figure 10.15 Antipredator fence surrounding Karori Sanctuary, Wellington, New Zealand
Controlling Introduced Vertebrates • Physical and Chemical Methods • -physical methods include trapping and shooting • Ex. Fig. 10.16 • -chemical methods mostly involve poisons added to bait • and non-target species may need to be temporarily removed • Ex Fig 10.17
Figure 10.16 Trapping introduced carp (Cyprinus sp.) from a freshwater lake
Figure 10.17 Eradication of introducedrats from some Galápagos Islands posed a risk to the rare Galápagos hawk, so they were captured prior to treatment and held in an aviary on a nearby island
Controlling Introduced Vertebrates • Biological Methods
Controlling Introduced Vertebrates • Control programs and unexpected consequences • -most control programs use more than one method • Ex. Eradication of introduced goats to Santiago Island in the Galapagos used both physical and biological means involving hunting to reduce the population followed by Judas goats Fig. 10.18 • -public sentiment may not favor eradication of vertebrates • Ex. Pig hunters in Hawaii oppose removal of feral pigs which have been identified as a major threat to forest ecosystems • -removal of introduced species may cause unexpected trophic shifts • Ex. Fig. 10.19 Removal of feral cats, which killed on average 33 sooty terns per night increased rat predation, which may affect terns
Figure 10.18 A Judas goat following release in South Australia is attracting the remaining feral goats that need be removed to complete eradication
Figure 10.19 Following a cat eradication program that was completed in 2004, the sooty tern population on Ascension Island rose, although not consistently and may now be limited by rats
Vertebrate species translocations • -translocation may be undertaken for threatened species and is more common in vertebrates than invertebrates or plants • -long been used by fish and game managers and is referred to as stocking • -IUCN has developed guidelines for translocation and categorize them into three groups: • 1.
Vertebrate species translocations • -translocations should be assessed thoroughly Fig. 10.20 • -recovery and restoration teams should also consider the attitudes of local people towards translocation • -most desirable source for translocations are wild populations with ecological and genetic characteristics similar to those of the original population • -may want a mix of individuals from several different source populations to minimize founder effects
Figure 10.20 Questions to guide species translocation decision making
Figure 10.22 A rare brush-tailed rock wallaby joey in the pouch of a yellow-footed rock wallaby is being cross-fostered at the Adelaide Zoo (Australia)
Releases • -poor-quality habitat at release sites can make a translocation fail • -since it may be difficult to gauge all factors of a quality habitat, restorers may use insurance populations-a population of an endangered species established in a location presumed to be temporary, remaining there until habitat conditions in permanent reintroduction sites are suitable for sustaining the species • Ex. Fig. 10.23 • -emergency translocations or rescues may require vertebrates to be treated before release Fig. 10.24
Figure 10.23 The takahe, a grassland bird from New Zealand’s South Island, was saved from extinction by establishing insurance populations on small offshore islands while invasive plants were removed and restoration of permanent sites occurred.
Figure 10.24 Following major oil spills, oil-coated birds like this African penguin (Spheniscusdemersus) are often removed from the contaminated area, cleaned, and released
Releases • -transition to release site is hazardous and many die soon after release due to stress and predation • -can be countered by confining animals to a small area on site for a short time and providing food, water, and time to adjust to new surroundings=soft release • Figs, 10.25-10.27
Figure 10.25 Peregrine falcons (Falco peregrinus) reintroduced to the New River Gorge National Park (West Virginia, U.S.) at a site where they receive food and shelter as they fledge
Figure 10.26 Acclimating spotfin chub prior to release in the Cheoah River (U.S.)
Figure 10.27 Breeding colonies of fluttering shearwaters and diving petrels were restored at Mana Island by translocating nestlingsand providing for them until they fledge. Vocalizations were broadcast from suitable nesting sites using sound systems so returning birds can locate sites more readily.
Figure 10.28 Fish in small streams are often surveyed using a backpack-mounted electroshocker
Figure 10.29 Invasion of Mimosa pigrainto a wet grassland (marshland) of Eleocharis spp. reduces habitat suitability for water birds
Figure 10.30 Biologists in Tram Chim National Park periodically map the spatial extent of the invasive species Mimosa pigra so that they can monitor changes in its distribution
