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1.
Nature ; 506(7487): 216-20, 2014 Feb 13.
Article in English | MEDLINE | ID: mdl-24499817

ABSTRACT

In line with global targets agreed under the Convention on Biological Diversity, the number of marine protected areas (MPAs) is increasing rapidly, yet socio-economic benefits generated by MPAs remain difficult to predict and under debate. MPAs often fail to reach their full potential as a consequence of factors such as illegal harvesting, regulations that legally allow detrimental harvesting, or emigration of animals outside boundaries because of continuous habitat or inadequate size of reserve. Here we show that the conservation benefits of 87 MPAs investigated worldwide increase exponentially with the accumulation of five key features: no take, well enforced, old (>10 years), large (>100 km(2)), and isolated by deep water or sand. Using effective MPAs with four or five key features as an unfished standard, comparisons of underwater survey data from effective MPAs with predictions based on survey data from fished coasts indicate that total fish biomass has declined about two-thirds from historical baselines as a result of fishing. Effective MPAs also had twice as many large (>250 mm total length) fish species per transect, five times more large fish biomass, and fourteen times more shark biomass than fished areas. Most (59%) of the MPAs studied had only one or two key features and were not ecologically distinguishable from fished sites. Our results show that global conservation targets based on area alone will not optimize protection of marine biodiversity. More emphasis is needed on better MPA design, durable management and compliance to ensure that MPAs achieve their desired conservation value.


Subject(s)
Conservation of Natural Resources/statistics & numerical data , Ecology/statistics & numerical data , Ecosystem , Fisheries/statistics & numerical data , Fishes/physiology , Animals , Aquatic Organisms/physiology , Biodiversity , Biomass , Conservation of Natural Resources/economics , Conservation of Natural Resources/legislation & jurisprudence , Conservation of Natural Resources/methods , Coral Reefs , Ecology/economics , Ecology/legislation & jurisprudence , Ecology/methods , Fisheries/legislation & jurisprudence , Fisheries/standards , Marine Biology/economics , Marine Biology/legislation & jurisprudence , Marine Biology/methods , Marine Biology/statistics & numerical data , Seawater , Sharks , Silicon Dioxide , Time Factors
2.
Arch Insect Biochem Physiol ; 58(1): 1-16, 2005 Jan.
Article in English | MEDLINE | ID: mdl-15599938

ABSTRACT

Gene expression and immunolocalisation studies have determined that the helicostatins are brain-gut peptides in larvae of the lepidopteran, Helicoverpa armigera. Mapping of the distribution of these peptides in the nervous system and alimentary canal has provided evidence for multifunctional regulatory roles. In situ hybridisation studies have shown that the helicostatin precursor gene is expressed in neurones of the central and stomatogastric nervous systems, and endocrine cells of the midgut demonstrating that the helicostatins are true brain-gut peptides. Antisera raised against Leu-callatostatin 3 (ANRYGFGL-NH(2)), a peptide isolated from the blowfly, Calliphora vomitoria was used to map the distribution of allatostatin-like immunoreactive (Ast-ir) material in H. armigera to elucidate possible functions of the helicostatins. In situ hybridisation studies verified that the helicostatin precursor gene is expressed in neurones shown to contain Ast-ir, providing strong evidence that the Ast-ir material is helicostatins. Extensive immunoreactive axonal projections into complex regions of neuropile indicate that the helicostatins may have a neuromodulatory role in the brain and segmental ganglia of the ventral nerve cord. The presence of large amounts of immunoreactive material in axons within the corpora cardiaca (CC) and transverse nerves of the perisympathetic nervous system, two known neurohaemal organs, provides evidence for a neurohormonal role. The corpora allata (CA) were innervated only sparsely by Ast-ir axons suggesting that the CA are not a neurohaemal release site or a target. Thus, it is unlikely that the helicostatins regulate juvenile hormone (JH) biosynthesis or release. Ast-ir axons extended from the frontal ganglion through the recurrent nerve and many branches were closely associated with muscles of the foregut, stomodeal valve, and anterior midgut, implicating helicostatins in regulation of foregut motility. Ast-ir material was also present in nerves associated with muscles of the pyloric valve and rectum, and in endocrine cells of the midgut.


Subject(s)
Insect Hormones/analysis , Moths/chemistry , Peptides/analysis , Animals , Central Nervous System/chemistry , Digestive System/chemistry , Digestive System/cytology , Digestive System/innervation , Enteroendocrine Cells/chemistry , Gene Expression , Immunohistochemistry , In Situ Hybridization , Moths/anatomy & histology , Neuropeptides/analysis , Neurosecretory Systems/chemistry
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