Juvenile Recruitment of Oak Toads (Anaxyrus quercicus) Varies with Time-Since-Fire in Seasonal Ponds

2015 ◽  
Vol 49 (3) ◽  
pp. 364-370 ◽  
Author(s):  
Clay F. Noss ◽  
Betsie B. Rothermel
Author(s):  
Dalilla da Silva Salvati ◽  
Júlia Fernandes Perroca ◽  
Sabrina Morilhas Simões ◽  
Antonio Leão Castilho ◽  
Rogerio Caetano da Costa

AbstractThe study characterized the structure of juveniles and sub-adults of Farfantepenaeus brasiliensis and F. paulensis in the Cananéia-Iguape estuarine lagoon system and its adjacent coastal area by evaluating the period of juvenile recruitment, sex ratio, growth, longevity, natural mortality, and development time until the late juvenile phase. Samples were collected from July 2012 to June 2014. Shrimps were identified by species and sex, and measured (carapace length – CL mm); 889 individuals of F. brasiliensis and 848 of F. paulensis were analysed. Females were more abundant than males for both species. The growth parameters of F. brasiliensis were: CL∞ = 45.5 mm, k = 1.8 year−1 for males and CL∞ = 55.2 mm, k = 1.6 year−1 for females; longevity of 2.52 years (males) and 2.88 years (females); and natural mortality of 1.71 (males) and 1.55 (females). For F. paulensis, the following values were observed: CL∞ = 40.7 mm, k = 2.3 year−1 for males and CL∞ = 56.5 mm, k = 1.9 year−1 for females; longevity of 2.04 years (males) and 2.37 years (females); and natural mortality of 2.39 (males) and 2.05 (females). The juvenile recruitment of both species peaked in January 2014. The development time until late juvenile phase was ~7 months (F. brasiliensis) and ~5 months (F. paulensis). Even though the highest abundance of juveniles did not occur in the closed season, fishing is forbidden in the estuarine area and the migration towards the adult population occurred close to or even during the closed season.


Author(s):  
Jemima Connell ◽  
Mark A. Hall ◽  
Dale G. Nimmo ◽  
Simon J. Watson ◽  
Michael F. Clarke

2020 ◽  
Vol 112 ◽  
pp. 106094
Author(s):  
Carolina Veronese Corrêa da Silva ◽  
Camila da Silva Goldas ◽  
Wesley Dáttilo ◽  
William Dröse ◽  
Milton de Souza Mendonça ◽  
...  

Wetlands ◽  
2022 ◽  
Vol 42 (1) ◽  
Author(s):  
Kathryn L. Hofmeister ◽  
Sue L. Eggert ◽  
Brian J. Palik ◽  
David Morley ◽  
Emily Creighton ◽  
...  

2018 ◽  
Vol 46 (2) ◽  
pp. 314-329 ◽  
Author(s):  
Adriana Ferreira ◽  
Ana Oeda ◽  
Patricia Oliveira ◽  
Adriano Prysthon ◽  
Roberto Valladao ◽  
...  

2017 ◽  
Vol 26 (10) ◽  
pp. 866 ◽  
Author(s):  
Tara E. Penman ◽  
Jane G. Cawson ◽  
Simon Murphy ◽  
Thomas J. Duff

Messmate stringybark is common in forests across south-eastern Australia. The bark of these trees is persistent and produces firebrands that contribute to house loss and the difficulty of fire suppression during wildfires. The trees typically survive fire with the amount of bark depleted. We compared two common methods to assess messmate bark fuels: (1) field-based hazard assessment, and (2) desk-based assessment using mapped time since fire. Our measurements included space-for-time field surveys and laboratory flammability tests. Although several physical properties of bark could be approximated from both assessment methods, some bark properties important to flammability were not captured. Ignitability was found to be dependent on the amount of char on bark fragments and could be predicted by the site assessment methods, whereas sustainability was dependent on bark fragment dimensions and could not be predicted by current methods. Bark fragment properties were found to be partially a function of tree size. Overall, these findings indicate that current bark assessment methods do not capture all the key bark properties that contribute to messmate bark’s flammability. Further research is warranted to improve bark assessment methods so they better reflect bark’s contribution to fire behaviour.


2018 ◽  
Vol 16 (3) ◽  
Author(s):  
Marcelo Loureiro ◽  
Rafael de Sá ◽  
Sebastián W. Serra ◽  
Felipe Alonso ◽  
Luis Esteban Krause Lanés ◽  
...  

ABSTRACT The family Rivulidae is the fourth most diverse clade of Neotropical fishes. Together with some genera of the related African family Nothobranchiidae, many rivulids exhibit a characteristic annual life cycle, with diapausing eggs and delayed embryonic development, which allows them to survive in the challenging seasonal ponds that they inhabit. Rivulidae also includes two species known as the only the self-fertilizing vertebrates and some species with internal fertilization. The first goal of this article is to review the systematics of the family considering phylogenetic relationships and synapomorphies of subfamilial clades, thus unifying information that is dispersed throughout the literature. From this revision, it is clear that phylogenetic relationships within Rivulidae are poorly resolved, especially in one of the large clades that compose it, the subfamily Rivulinae, where conflicting hypotheses of relationships of non-annual and annual genera are evident. The second goal of this work is to present an updated phylogenetic hypothesis (based on mitochondrial, nuclear, and morphological information) for one of the most speciose genus of Rivulidae, Austrolebias. Our results confirm the monophyly of the genus and of some subgeneric clades already diagnosed, but propose new relationships among them and their species composition, particularly in the subgenus Acrolebias.


<em>Abstract</em> .—Basic research on the settlement and postsettlement ecology of spiny lobster <em>Panulirus argus </em> has led to an application with the potential to replace lost natural refuge with artificial shelters intended for the vulnerable small juvenile stages. We began investigating ecological processes regulating juvenile spiny lobster recruitment in the Florida nursery in the mid-1980s. An unprecedented massive die-off of sponges in the middle Florida Keys followed cyanobacterial blooms in 1991–1993, ultimately affecting about 300 km2 of a region providing approximately one-fifth of total juvenile recruitment. Before 1991, crevices in sponges provided diurnal refuge from predators for about 70% of juveniles <50 mm carapace length. On the basis of sampling done before and after sponge loss, we estimated that juvenile abundance declined by 30–50% on spongeless sites without alternative shelter, resulting in a decrease of annual nurserywide potential of up to 10%. Results of a field experiment evaluating the relative influences of the magnitude of settlement and availability of crevice shelter on juvenile recruitment, fortuitously begun before the sponge die-off, showed that juvenile survival and abundance were sustained on small 0.02- to 0.07-ha test sites provided with supplemental artificial shelters (slotted concrete blocks). In the absence of sponges, survival of microwire-tagged juveniles on the shelter-supplemented sites was about six times higher than that on unsupplemented sites. On the basis of our earlier ecological findings, we devised a feasibility study to test whether the artificial shelters could replace lost sponge shelter for juvenile lobsters on a large scale. It took the form of a field experiment using 240 shelters spread over 1-ha sites located amid hard substrate denuded of sponges. The shelters provided substitute crevices, supporting juvenile lobster recruitment approximating that in areas with good sponge cover. This outcome exemplifies the essential value of initial basic research that provides understanding of the ecological processes regulating individual survival and, ultimately, the character and dynamics of the fishery population. Such an approach, and the information it provides, is necessary to successful rehabilitation of essential habitat or restocking of natural populations. Moreover, conducting basic research can help prevent the waste of precious time, funds, income, and human effort that typically has occurred in past failed attempts that were undertaken with insufficient knowledge. We urge the fisheries-ecology discipline and support agencies to promote strongly the primacy of research on basic processes.


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