Use of semi-intensive shrimp farms as alternative foraging areas by migratory shorebird populations in tropical areas

2018 ◽  
Vol 29 (2) ◽  
pp. 263-276 ◽  
Author(s):  
JUAN G. NAVEDO ◽  
GUILLERMO FERNÁNDEZ
Keyword(s):  
Coastal Wetlands ◽  
High Tide ◽  
Significant Proportion ◽  
Abundant Species ◽  
Natural Habitats ◽  
Western Sandpiper ◽  
Tropical Areas ◽  
Northwestern Mexico ◽  
Breeding Seasons ◽  
Shrimp Farms

SummaryEvaluating the ability of anthropogenic habitats to serve as surrogates for natural habitats is an increasingly relevant issue in conservation biology. This issue is especially urgent in tropical coastal wetlands that support large concentrations of migratory shorebird populations and are under pressure from development. Here we evaluated the species composition, abundance, and habitat use of Nearctic migratory shorebirds using recently harvested aquaculture ponds during two non-breeding seasons at shrimp farms surrounding Bahía Santa María (BSM), northwestern Mexico. We also estimated shorebird densities at intertidal units in BSM during and after the harvesting season to explore the connectivity with shrimp farms. Over 25,000 individuals of 25 shorebird species used the surveyed farms (∼13% of shrimp-farm development in BSM; 2014–2015: 10 farms, 994 ha; 2015–2016: 8 farms, 924 ha) during the harvest season. The most abundant species were: Western Sandpiper Calidris mauri, Willet Tringa semipalmata, Marbled Godwit Limosa fedoa, dowitchers Limnodromus spp., Black-necked Stilt Himantopus mexicanus and American Avocet Recurvirostra americana. Numbers of birds decreased as the harvest cycle progressed. Most birds (> 70%) were foraging on the ponds, regardless of tidal stage, while numbers increased during high tide for the most abundant species. At surveyed intertidal areas, shorebird densities were overall similar within and between non-breeding seasons. These results indicate that shrimp farms offer ephemeral but consistent foraging habitats used by non-breeding shorebirds, even in vast coastal wetlands offering a high availability of natural intertidal mudflats. Assuming a similar shorebird use in other shrimp ponds not surveyed within BSM, a significant proportion (> 1% of the biogeographic population) of Willet, Marbled Godwit, and Western Sandpiper, as well as imperilled Red Knot Calidris canutus, might use shrimp farms throughout the harvesting season. Before including current semi-intensive shrimp farms within management plans of BSM, further research is mandatory to assess their utility as alternative foraging habitats for shorebird conservation at tropical areas.

scholarly journals Trouble in Paradise? A comparison of 1953 and 2005 benthonic foraminiferal seafloor assemblages at the Ibis Field, offshore eastern Trinidad, West Indies

2006 ◽  
Vol 25 (2) ◽  
pp. 157-164 ◽  
Author(s):  
Brent Wilson
Keyword(s):  
Relative Abundance ◽  
Nutrient Enrichment ◽  
Abundant Species ◽  
Nutrient Supply ◽  
South American ◽  
Sufficient Time ◽  
Phytoplankton Primary Production ◽  
Environmental Perturbations ◽  
Run Off ◽  
Shrimp Farms

Abstract. Foraminiferal communities are not static, but change in response to environmental perturbations. Given sufficient time, the change will be recorded in the total (live+dead) seafloor assemblage, from which valuable information regarding environmental trends can be obtained by re-sampling assemblages at the decadal scale.The seafloor assemblage in the 5 km × 6 km Ibis Field, off southeast Trinidad, first surveyed in 1953, was re-examined in 2005. The fauna had changed markedly between the surveys. Overall increases in the proportional abundances of Uvigerina subperegrina, Ammonia pauciloculata/Rolhausenia rolhauseni and Pseudononion atlanticum indicate an increase in nutrient supply that apparently killed off Cibicidoides pseudoungerianus and Miliolinella subrotunda, and reduced the relative abundance of Hanzawaia concentrica, but did not affect the relative abundance of Cancris sagrai. As shown by similar 1953 and 2005 planktonic/benthonic foraminiferal ratios, the increased nutrient supply impacted on both surface and bottom waters.Of the six most abundant species in 2005, five showed the same general biogeographical distributions within the field in 1953 and 2005. However, whereas the proportional abundance of Uvigerina subperegrina in 1953 increased southwards, in 2005 it increased northwards.Trinidad cannot be the source for the nutrient enrichment: the island lies down-current from the Ibis Field. Sources must therefore be sought up-current and to the southeast, in the Amazon, Essequibo and Orinoco river basins, or along the South American shoreline. It is speculated that the nutrient enrichment may be a consequence of increased phytoplankton primary production associated with nitrogen-rich run-off from South American sugarcane plantations, or from flushing of organic carbon from poorly regulated sewage systems or shrimp farms in South America.

scholarly journals Bees use anthropogenic habitats despite strong natural habitat preferences

2018 ◽  
Author(s):  
Miguel Á. Collado ◽  
Daniel Sol ◽  
Ignasi Bartomeus
Keyword(s):  
Habitat Loss ◽  
Natural Habitat ◽  
Habitat Preferences ◽  
Abundant Species ◽  
Comprehensive Analysis ◽  
Natural Habitats ◽  
Large Dataset ◽  
Anthropogenic Habitats ◽  
Bee Diversity ◽  
Northeast Usa

ABSTRACTHabitat loss and alteration is widely considered one of the main drivers of the current loss of pollinator diversity. Unfortunately, we still lack a comprehensive analysis of habitat importance, use and preference for major groups of pollinators. Here, we address this gap analysing a large dataset of 15,762 bee specimens (more than 400 species) across northeast USA. We found that natural habitats sustain the highest bee diversity, with many species strongly depending on such habitats. By characterizing habitat use and preference for the 45 most abundant species, we also show that many bee species can use human-altered habitats despite exhibiting strong and clear preferences for forested habitats. However, only a few species appear to do well when the habitat has been drastically modified. We conclude that although altered environments may harbor a substantial number of species, preserving natural areas is still essential to guarantee the conservation of bee biodiversity.

scholarly journals Animal origins of SARS coronavirus: possible links with the international trade in small carnivores

2004 ◽  
Vol 359 (1447) ◽  
pp. 1107-1114 ◽  
Author(s):  
Diana Bell ◽  
Scott Roberton ◽  
Paul R. Hunter
Keyword(s):  
Significant Proportion ◽  
Interdisciplinary Approach ◽  
Wildlife Trade ◽  
Human Populations ◽  
Sars Coronavirus ◽  
Natural Habitats ◽  
Biodiversity Crisis ◽  
International Borders ◽  
Animal Populations ◽  
International Wildlife Trade

The search for animal host origins of severe acute respiratory syndrome (SARS) coronavirus has so far remained focused on wildlife markets, restaurants and farms within China. A significant proportion of this wildlife enters China through an expanding regional network of illegal, international wildlife trade. We present the case for extending the search for ancestral coronaviruses and their hosts across international borders into countries such as Vietnam and Lao People's Democratic Republic, where the same guilds of species are found on sale in similar wildlife markets or food outlets. The three species that have so far been implicated, a viverrid, a mustelid and a canid, are part of a large suite of small carnivores distributed across this region currently overexploited by this international wildlife trade. A major lesson from SARS is that the underlying roots of newly emergent zoonotic diseases may lie in the parallel biodiversity crisis of massive species loss as a result of overexploitation of wild animal populations and the destruction of their natural habitats by increasing human populations. To address these dual threats to the long–term future of biodiversity, including man, requires a less anthropocentric and more interdisciplinary approach to problems that require the combined research expertise of ecologists, conservation biologists, veterinarians, epidemiologists, virologists, as well as human health professionals.

Variation in maternal attendance patterns and pup behaviour in a declining population of Steller sea lions (Eumetopias jubatus)

1997 ◽  
Vol 75 (8) ◽  
pp. 1241-1246 ◽  
Author(s):  
Wendy R. Hood ◽  
Kathryn A. Ono
Keyword(s):  
Prey Availability ◽  
Population Decline ◽  
High Tide ◽  
Eumetopias Jubatus ◽  
Steller Sea Lions ◽  
Breeding Area ◽  
Foraging Effort ◽  
Sea Lions ◽  
Attendance Patterns ◽  
Breeding Seasons

Maternal attendance patterns of lactating female Steller sea lions (Eumetopias jubatus) and the activity budgets of pups on Año Nuevo Island, California, were compared between the 1973 and 1992 breeding seasons to investigate temporal changes in behaviour that may be associated with population decline. Females were absent from the breeding area longer in 1992, which may reflect increased foraging effort. Pups also spent significantly less time sucking and more time swimming in 1992. Suckling time is correlated with milk intake in some otariid species, thus the decreased amount of time 1992 pups spent sucking could reflect a reduction in the total volume of milk produced by females. Pups in 1992 are likely to have spent more time swimming than pups in 1973 because high tide covered a greater proportion of the study site in 1992 than in 1973. An increase in time females spent at sea and a decrease in time pups spent sucking are consistent with behavioural changes associated with reduced prey availability.

A painter in the Bering Sea: Henry Wood Elliott and the northern fur seal

Polar Record ◽  
2013 ◽  
Vol 50 (3) ◽  
pp. 311-318
Author(s):  
Robert McCracken Peck
Keyword(s):  
Abundant Species ◽  
Historical Record ◽  
Fur Seals ◽  
Commercial Harvest ◽  
Dramatic Decline ◽  
Fur Seal ◽  
Pribilof Islands ◽  
Breeding Seasons ◽  
The U.S

ABSTRACTHenry Wood Elliott (1846–1930), a U.S. Treasury official assigned to monitor the harvest of northern fur seals on the Pribilof Islands in the 1870s, became a self-taught expert on, and defender of, the species. His careful documentation of the seals’ breeding behaviour, and of their commercial harvest, complemented by hundreds of detailed and evocative watercolours, provides a unique record of this once abundant species and the lucrative industry that revolved around it. Elliott's outspoken lobbying on behalf of the seals’ protection is often credited with saving the species from extinction. His paintings of the seals, the seal harvest, and life on the Pribilof Islands in the second half of the nineteenth century constitute an unmatched historical record of this remote region.Elliott was able to witness two full breeding seasons (and harvesting) of the fur seals during his initial stay on the Pribilofs from April 1872 to October 1873. He returned to the islands to conduct a follow-up census of the seals, on behalf of the U.S. Government, in the summer of 1874. He traveled there unofficially and at his own expense in 1876. His fourth trip to the Pribilofs was in the spring of 1890 (again on behalf of the U.S. Department of the Treasury), in response to news of a dramatic decline of the seal populations. In April, 1891, because of his public revelation of mismanagement of the fur seal harvest, Elliott was fired by the Treasury. He continued his tireless lobbying on behalf of the fur seals as a private citizen for the rest of his life. He visited the Pribilofs for the last time on behalf of the House Committee on Expenditures in the Department of Commerce and Labor in the summer of 1913. Born in Cleveland Ohio on November 13, 1846, Elliott died in Seattle Washington on May 25, 1930.

Asian water monitors (Varanus salvator) remain common in Peninsular Malaysia, despite intense harvesting

2019 ◽  
Vol 46 (3) ◽  
pp. 265 ◽  
Author(s):  
Syarifah Khadiejah ◽  
Norazlinda Razak ◽  
Georgia Ward-Fear ◽  
Richard Shine ◽  
Daniel J. D. Natusch
Keyword(s):  
International Trade ◽  
Sustainable Use ◽  
Significant Proportion ◽  
Cost Effective ◽  
Peninsular Malaysia ◽  
Natural Habitats ◽  
Wild Fauna ◽  
Varanus Salvator ◽  
In The Wild ◽  
Asian Water

Context Each year, between 50000 and 120000 Asian water monitors (Varanus salvator, to >2 m total length) are harvested from the wild in Peninsular Malaysia for their skins. Under the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES), international trade is allowable only if it is sustainable. Aims To assess the sustainability of Malaysia’s harvest of water monitors by quantifying the abundance and demography of V. salvator in the wild, and to develop cost-effective methods for estimating the parameters needed to evaluate sustainability. Methods We conducted trapping surveys to determine the abundance, population demography and density of V. salvator in four habitat types in five states in Peninsular Malaysia in 2010, 2011, 2012 and 2018. Key results Of 1025 lizards captured, only 63% (mostly females) were within the preferred body-size range exploited for commercial trade. Densities were high (37–372 lizards km–2 based on estimated population sizes; 1–35 lizards km–2 based on number of animals captured). Anthropogenic habitats (e.g. oil palm plantations) contained denser populations of monitors than did natural habitats where no hunting occurs, but mean body sizes were smaller. Conclusions Despite intensive harvesting for many decades, V. salvator remains abundant and widespread. Harvesting alters the demographic structure of lizard populations, but harvests of V. salvator in Malaysia are likely to be sustainable because a significant proportion of the population is not exploited. Implications Ongoing monitoring is required to continually reassess harvest sustainability. For this purpose, relatively simple population approaches, such as line-trapping transects to elucidate relative abundances, can provide important data on the makeup of hunted populations of water monitors more cost-effectively than can mark–recapture studies for assessments of sustainable use of these economically important lizards.

Occurrence of the entomopathogenic fungi Metarhizium anisopliae and Beauveria bassiana in soils from temperate and near-northern habitats

1998 ◽  
Vol 76 (7) ◽  
pp. 1198-1204 ◽  
Author(s):  
Michael J Bidochka ◽  
June E Kasperski ◽  
Geoffrey AM Wild
Keyword(s):  
Beauveria Bassiana ◽  
Entomopathogenic Fungi ◽  
Metarhizium Anisopliae ◽  
Population Biology ◽  
Galleria Mellonella ◽  
Natural Habitat ◽  
Abundant Species ◽  
Fungal Population ◽  
Natural Habitats ◽  
Agricultural Habitat

The occurrence of deuteromycetous entomopathogenic fungi was examined in 266 soil samples representing 86 locations across temperate and near northern habitats in Ontario, Canada. Entomopathogenic fungi were isolated by baiting the soil with waxworm larvae, Galleria mellonella L., and incubating at 8, 15, or 25°C. Entomopathogenic fungi were isolated from 91% of the locations sampled across Ontario. The most abundant species were Metarhizium anisopliae (Metschn.) Sorok. (357 isolates) and Beauveria bassiana (Bals.) Vuill. (187 isolates). Thirteen isolates of Paecilomyces spp. were also found. Beauveria bassiana was isolated more frequently in soils from near northern locations, relative to M. anisopliae. Beauveria bassiana was isolated more frequently from larvae baited in soils incubated at 8 and 15°C, while M. anisopliae was isolated most frequently at 25°C. Thus, B. bassiana is more psychrophilic than M. anisopliae. From 47 of the locations in a temperate area (southern Ontario and the Kawartha Lakes region), two sites, one from an agricultural habitat and one from a natural habitat, were sampled within 1 km of each other. In these locations, B. bassiana was predominantly recovered more often from soils of natural habitats, while M. anisopliae was recovered more often in agricultural habitats. The occurrence of M. anisopliae and B. bassiana was not related to soil type or pH.Key words: Metarhizium, Beauveria, entomopathogenic fungi, fungal population biology, soil ecology.

scholarly journals Gastropods in the Intertidal Shore of Kota Kinabalu, Sabah (Malaysian Borneo)

2021 ◽  
Vol 11 (1) ◽  
pp. 9-23
Author(s):  
JOHN MADIN ◽  
BALU-ALAGAR VENMATHI MARAN ◽  
SUET-MUN HO
Keyword(s):  
Urban Areas ◽  
Natural Habitat ◽  
Abundant Species ◽  
Habitat Destruction ◽  
Anthropogenic Factors ◽  
Natural Habitats ◽  
Coral Rubble ◽  
Ecological Benefits ◽  
The City ◽  
Malaysian Borneo

Intertidal gastropods provide numerous ecological benefits and are responsible for the dynamics of the intertidal shores habitat and its community assemblages. This study examined the community structure of gastropods in the intertidal shore located near the city of Kota Kinabalu, the capital of Sabah where coastal areas are rapidly developed for various purposes and consequently destroying natural habitats.  A total of 36 gastropods species from 15 families were recorded.  The Planaxis sulcatus was the most abundant species with a density of 480 ind. m-2 followed by Nodilittorina pyramidalis (182 ind. m-2) and Cellana radiata (97 ind. m-2) respectively.  The number of species and their abundance, respectively, are almost three times lower than the number ever recorded for intertidal shores located in non-urban areas or remote locations.  This suggests that the rapidly growing coastal urban areas threatening the diversity and abundance of intertidal gastropods. The density of gastropod (i.e. P. sulcatus & N. pyramidalis) was significantly (p<0.05) high at the lower intertidal shore where slope gradient is steeper with rocks and crevices are the major component of substrates compared to the upper or middle zone which is flatter and composed mainly of coral rubble and sand. Our study suggests that gastropod communities in intertidal shores located adjacent to the urban areas are threatened especially by anthropogenic factors such as frequent human visitations and modification of natural habitat. Future development in the intertidal shore should minimise habitat destruction and should consider infrastructures that encourage gastropod populations to grow and highlighting their ecological role for conservation reasons.

scholarly journals Diet ecology of tigers and leopards in Chhattisgarh, central India

2020 ◽  
Vol 12 (3) ◽  
pp. 15289-15300
Author(s):  
Krishnendu Basak ◽  
Moiz Ahmed ◽  
M. Suraj ◽  
B.V. Reddy ◽  
O.P. Yadav ◽  
...  
Keyword(s):  
Prey Availability ◽  
Central India ◽  
Abundant Species ◽  
Wild Ungulates ◽  
Natural Habitats ◽  
Term Survival ◽  
Long Term Survival ◽  
Large Predator ◽  
Large Predators

Wild prey base is a potential regulatory parameter that supports successful propagation and secured long term survival of large predators in their natural habitats. Therefore, low wild prey availability with higher available livestock in or around forest areas often catalyzes livestock depredation by predators that eventually leads to adverse situations to conservation initiatives. Thus understanding the diet ecology of large predators is significant for their conservation in the areas with low prey base. The present study reports the diet ecology of tiger and leopard in Udanti Sitanadi Tiger Reserve and Bhoramdeo Wildlife Sanctuary, in central India to know the effect of wild prey availability on prey predator relationship. We walked line transects to estimate prey abundance in the study areas where we found langur and rhesus macaque to be the most abundant species. Scat analysis showed that despite the scarcity of large and medium ungulates, tiger used wild ungulates including chital and wild pig along with high livestock utilization (39%). Leopards highly used langur (43–50 %) as a prime prey species but were observed to exploit livestock as prey (7–9 %) in both the study areas. Scarcity of wild ungulates and continuous livestock predation by tiger and leopard eventually indicated that the study areas were unable to sustain healthy large predator populations. Developing some strong protection framework and careful implementation of the ungulate augmentation can bring a fruitful result to hold viable populations of tiger and leopard and secure their long term survival in the present study areas in central India, Chhattisgarh. 

scholarly journals Population Densities and Community Structure of Birds Breeding in a Suburban Wooded Grassland in the Highveld of Lesotho

2019 ◽  
Vol 53 (2) ◽  
pp. 155-164
Author(s):  
G. Kopij
Keyword(s):  
Community Structure ◽  
Diversity Index ◽  
Mapping Method ◽  
Feeding Guilds ◽  
Avian Community ◽  
Natural Habitats ◽  
Turtle Dove ◽  
Breeding Seasons ◽  
Avian Community Structure

Abstract The mapping method was employed to study avian community structure in relation to rainfall in a town suburb in Highveld grassland in southern Africa. Studies were conducted in two breeding seasons: 1998, with dry spring; and 2001, with close to average spring rainfall. The total rainfall in 1998 was 1254 mm, while in 2001 it was 1445 mm, in both years much above the long-term annual average (866 mm). The avian community remained remarkably similar in both years, both in respect to the number of species (44 in 1998 and 53 in 2001), and dominance relationships. The Simpson’s Diversity Index was high and also very similar in 1998 and 2001 (D = 0.91; 0.93 respectively). In all years, dominant species included the Laughing Dove, Grey-headed Sparrow, Speckled Dove, Cape Turtle-Dove and Common Fiscal. The Southern Red Bishop in 2001 was also in the group of dominants. Significant differences were noted in the overall density of all birds, but contrary to expectation density was higher in 1998, with lower rainfall, than in 2001, with higher rainfall. The proportions of nesting and feeding guilds were similar in both years compared, except for the granivores, which were proportionally more common in 1998 than in 2001. This difference was mainly due to the Laughing Dove and Grey-headed Sparrow. Generally, it appears that the suburban avian community is more stable and more diverse than neighbouring communities in the natural habitats.

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