Experimental Analysis of an Early Life-History Stage: Water Loss and Migrating Hatchling Turtles

Population growth involves demographic bottlenecks that regulate recruitment success during various early life-history stages. The success of each early life-history stage can vary in response to population density, interacting with intrinsic (e.g. behavioural) and environmental (e.g. competition, predation) factors. Here, we used the common reef-building coral Acropora millepora to investigate how density-dependence influences larval survival and settlement in laboratory experiments that isolated intrinsic effects, and post-settlement survival in a field experiment that examined interactions with environmental factors. Larval survival was exceptionally high (greater than 80%) and density-independent from 2.5 to 12 days following spawning. By contrast, there was a weak positive effect of larval density on settlement, driven by gregarious behaviour at the highest density. When larval supply was saturated, settlement was three times higher in crevices compared with exposed microhabitats, but a negative relationship between settler density and post-settlement survival in crevices and density-independent survival on exposed surfaces resulted in similar recruit densities just one month following settlement. Moreover, a negative relationship was found between turf algae and settler survival in crevices, whereas gregarious settlement improved settler survival on exposed surfaces. Overall, our findings reveal divergent responses by coral larvae and newly settled recruits to density-dependent regulation, mediated by intrinsic and environmental interactions.

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Influences of spawning timing, water temperature, and climatic warming on early life history phenology in western Alaska sockeye salmon

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/cjfas-2017-0468 ◽

2019 ◽

Vol 76 (1) ◽

pp. 123-135 ◽

Cited By ~ 6

Author(s):

Morgan M. Sparks ◽

Jeffrey A. Falke ◽

Thomas P. Quinn ◽

Milo D. Adkison ◽

Daniel E. Schindler ◽

...

Keyword(s):

Life History ◽

Water Temperature ◽

Early Life ◽

Sockeye Salmon ◽

Early Life History ◽

Life History Stage ◽

Climatic Warming ◽

Temperature Regimes ◽

Close Proximity ◽

Lake Temperature

We applied an empirical model to predict hatching and emergence timing for 25 western Alaska sockeye salmon (Oncorhynchus nerka) populations in four lake-nursery systems to explore current patterns and potential responses of early life history phenology to warming water temperatures. Given the temperature regimes sockeye salmon experienced during development, we predicted hatching to occur in as few as 58 days to as many as 260 days depending on spawning timing and temperature. For a focal lake spawning population, our climate–lake temperature model predicted a water temperature increase of 0.7 to 1.4 °C from 2015 to 2099 during the incubation period, which translated to a hatching timing that was 16 to 30 days earlier. The most extreme warming scenarios shifted development to approximately 1 week earlier than historical minima and thus climatic warming may lead to only modest shifts in phenology during the early life history stage of this population. The marked variation in the predicted timing of hatching and emergence among populations in close proximity on the landscape may serve to buffer this metapopulation from climate change.

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Systematics of the combtooth blenny clade Omobranchus (Blenniidae: Omobranchini), with notes on early life history stages

Zootaxa ◽

10.11646/zootaxa.4369.2.7 ◽

2018 ◽

Vol 4369 (2) ◽

pp. 270 ◽

Cited By ~ 1

Author(s):

SEAN GIBBS ◽

PETER J. HUNDT ◽

ANDREA NELSON ◽

JOSHUA P. EGAN ◽

PRASERT TONGNUNUI ◽

...

Keyword(s):

Life History ◽

Early Life ◽

Phylogenetic Analyses ◽

Early Life History ◽

Morphological Characters ◽

Species Group ◽

Life History Stage ◽

Molecular Systematic ◽

Widespread Species ◽

Phylogeographic Break

The combtooth blenny (Blenniidae) genus Omobranchus contains small, cryptobenthic fishes common to nearshore habitats throughout the Indo-West Pacific. Recent molecular systematic studies have resolved Omobranchus as monophyletic but little research has been done to resolve species-level relationships. Herein, phylogenetic analyses of one mitochondrial (CO1) and four nuclear (ENC1, myh6, sreb2, and tbr1) genes provide evidence for the monophyly of Omobranchus and support for the elongatus and banditus species group. Sampling of multiple individuals from widespread species (O. ferox, O. punctatus, and O. elongatus) suggested that the Thai-Malay Peninsula is a phylogeographic break that may be a historic barrier to gene flow. Additionally, common meristics and other morphological characters are used to describe an early life history stage of O. ferox and O. punctatus.

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De novo assembly, characterization, functional annotation and expression patterns of the black tiger shrimp (Penaeus monodon) transcriptome

10.1101/280420 ◽

2018 ◽

Cited By ~ 1

Author(s):

Roger Huerlimann ◽

Nicholas M Wade ◽

Lavinia Gordon ◽

Juan D Montenegro ◽

Jake Goodall ◽

...

Keyword(s):

Life History ◽

Early Life ◽

Penaeus Monodon ◽

Early Life History ◽

Model Organisms ◽

Life History Stage ◽

Black Tiger Shrimp ◽

Shrimp Species ◽

Life History Stages ◽

Tiger Shrimp

AbstractThe black tiger shrimp (Penaeus monodon) remains the second most widely cultured shrimp species globally. However, issues with disease and domestication have seen production levels stagnate over the past two decades. To help identify innovative solutions needed to resolve bottlenecks hampering the culture of this species, it is important to generate genetic and genomic resources. Towards this aim, we have produced the most complete publicly available P. monodon transcriptome database to date. The assembly was carried out in multiple assemblers using 2×125 bp HiSeq data from PolyA selected, ribo-depleted RNA extracted from nine adult tissues and eight early life-history stages. In total, approximately 700 million high-quality sequence reads were obtained and assembled into 236,388 clusters. These were then further segregated into 99,203 adult tissue specific clusters, and 58,678 early life-history stage specific clusters. The final transcriptome had a high TransRate score of 0.37, with 88% of all reads successfully mapping back to the transcriptome. BUSCO statistics showed the assembly to be highly complete with low fragmentation, few genes missing, but higher redundancy or transcript duplication (Complete: 98.2% (Duplicated: 51.3%), Fragmented: 0.8%, Missing: 1.0%), and to greatly exceed the completeness of existing P. monodon transcriptomes. While annotation rates were low (approximately 30%), as is typical for a non-model organisms, annotated transcript clusters were successfully mapped to several hundred functional KEGG pathways. To help address the lack of annotation, transcripts were clustered into groups within tissues and early life-history stages, providing initial evidence for their roles in specific tissue functions, or developmental transitions. Additionally, transcripts of shrimp viruses previously not known to occur in Australia were also discovered. We expect the transcriptome to provide an essential resource to investigate the molecular basis of commercially relevant-significant traits in P. monodon and other shrimp species.

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