Fertilization efficiency and gamete viability in the ascidian Pyura praeputialis in Chile

Manríquez, Patricio H.; Castilla, Juan Carlos

doi:10.3354/meps08618

Cited by 8 publications

(14 citation statements)

References 29 publications

(49 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…However, the model projections of fishery implications of the Allee effect on broadcast spawners suggest that the effects may be too weak to be detected in stock-recruitment relationships (Lundquist & Botsford 2004). The published evidence suggests that fertilization success in intertidal P. praeputialis and related species is limited and drops to less than 10% over distances of a few meters (Marshall 2002;Manríquez & Castilla 2010). Moreover, recruitment takes place on the surface of conspecifics (Alvarado et al 2001;present study).…”

Section: Discussionmentioning

confidence: 83%

“…Seawater samples from the upper ten cm of the water column were collected using a plankton bilge pump equipped with a 50-μm elbow end (Castilla et al 2007;Manríquez & Castilla 2010;Fig. 2c).…”

Section: Monitoring Of Near-shore Larval Stagesmentioning

confidence: 99%

“…The extremely restricted distribution range of P. praeputialis inside the Bay of Antofagasta, and the concentration of its short-lived larvae (Clarke et al 1999) in near-shore waters Manríquez & Castilla 2010) allows for empirical testing, under natural conditions, as to whether or not changes in the intertidal abundances of adult individuals have an effect on the local abundances of con-specific larvae. Moreover, because in this species and other closely-related species recruitment takes place mainly on the surface of conspecifics (Alvarado et al 2001;Marshall 2002), the local recruitment should be driven by the reproductive output of the adjacent populations, selective larval behaviour at settlement and the amount of available substratum for settlement.…”

Section: Introductionmentioning

confidence: 99%

“…Hence, investigating the relationship between adult tunicate abundances and local abundances of larvae and recruits is particularly important in a species with short-lived larvae and reduced dispersive potential (Teske 2014). P. praeputialis is a hermaphrodite species that simultaneously sheds eggs and sperm through the atrial siphon and where fertilization takes place in the water column (Marshall 2002;Castilla et al 2007;Manríquez & Castilla 2010). Self-fertilization is not observed in P. praeputialis (Manríquez & Castilla 2010); therefore, cross-fertilization is the only mechanism that permits larval production.…”

Section: Introductionmentioning

confidence: 99%

“…P. praeputialis is a hermaphrodite species that simultaneously sheds eggs and sperm through the atrial siphon and where fertilization takes place in the water column (Marshall 2002;Castilla et al 2007;Manríquez & Castilla 2010). Self-fertilization is not observed in P. praeputialis (Manríquez & Castilla 2010); therefore, cross-fertilization is the only mechanism that permits larval production. Gonad index analysis in this species suggests the existence of a reproductive seasonality, but with presence of sexually mature individuals all year-round (Gutiérrez & Lay 1965;our own unp.…”

Section: Introductionmentioning

confidence: 99%

See 4 more Smart Citations

Empirical evidence for large‐scale human impact on intertidal aggregations, larval supply and recruitment of Pyura praeputialis around the Bay of Antofagasta, Chile

Manríquez¹,

Castilla

Ortíz

et al. 2016

Austral Ecology

View full text Add to dashboard Cite

In northern Chile, Pyura praeputialis is an invasive species inhabiting rocky intertidal and subtidal habitats restricted exclusively to the Bay of Antofagasta where it forms extensive aggregations. The negative impact of Pyura gathering on mid-intertidal abundances of this species has recently been reported at the south-eastern end of this bay. In the present study we have increased sampling sites to cover the entire bay toward the north-western end and the northern section, where a coastal marine reserve for the scallop fishery partially restricts shellfish gathering. Therefore, the sampling sites were chosen to represent different levels of shellfish gathering access along the northern shore of the bay. Long-term monitoring (1999)(2000)(2001)(2002)(2003)(2004)(2005)(2006)(2007)(2008)(2009)(2010)(2011)(2012)(2013)(2014) of changes in tunicate cover and the abundances of larvae and recruits at seven sites are reported. The opening of a remodelled artificial and recreational beach in 2012, on the central-eastern shore of the bay, has increased accessibility to rocky intertidal platforms that started to be massively visited by Pyura gatherers from the summer of 2013. This allowed for the implementation of an intensive short-term monitoring program of changes in tunicate cover and the abundances of their larvae and recruits. When gathering access was present the reduction in intertidal cover was generalized to the entire bay and followed by reductions in larvae and recruits. However, these reductions were not found in sites with more restricted gathering access. We conclude that continuous extraction by Pyura gatherers followed by reductions of conspecific larvae and recruits are the main drivers behind the reduced abundance of P. praeputialis in the entire bay of Antofagasta. Thus, if gathering is not stopped important ecosystem services provided by this tunicate in the bay may be threatened. Similar consequences may be expected if other massive and irreversible reductions in other species of the Pyura complex, that inhabit other coasts in the southern hemisphere, occur. The controversy concerning the impacts of invasive species and whether they cause negative, positive or neutral impacts to original ecosystems and fisheries is discussed.

show abstract

Section: Discussionmentioning

confidence: 83%

Section: Monitoring Of Near-shore Larval Stagesmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Empirical evidence for large‐scale human impact on intertidal aggregations, larval supply and recruitment of Pyura praeputialis around the Bay of Antofagasta, Chile

Manríquez¹,

Castilla

Ortíz

et al. 2016

Austral Ecology

View full text Add to dashboard Cite

show abstract

Effects of inter-annual temperature variability, including ENSO and post-ENSO events, on reproductive traits in the tunicatePyura praeputialis

Manríquez

Guíñez

Olivares

et al. 2018

Marine Biology Research

View full text Add to dashboard Cite

Ethical consideration in invasion ecology: A marine perspective

Bunting¹,

Coleman²

2013

Eco Management Restoration

View full text Add to dashboard Cite

Summary Biological introductions of species to regions outside their known natural distribution are considered a major threat to native marine biodiversity and a key consideration for ecological management. For most invasive species in marine systems, however, little is known about potential impacts. If we are to increase our knowledge of the processes and mechanisms behind the spread of nonindigenous species or determine economic or ecological impacts, manipulative ecological field experiments are the best way to unambiguously ascribe causal relationships. For studies of invasions, such research may result in species spread and the establishment of new viable populations. Is it ethical then, to take the risk of potentially modifying or endangering other species, populations or ecosystems? Is it possible to mitigate the risks? Or should invasion ecologists work under restrictions that limit their ability to fully assess the impact of invaders? Consideration of the ethics of experimentation is rarely carried out. As a consequence, we propose a decision model that includes possible risk of escape/establishment versus the value of the research to allow researchers and/or managers to critically evaluate what type of experimental approach is appropriate.

show abstract

Fertilization efficiency and gamete viability in the ascidian Pyura praeputialis in Chile

Cited by 8 publications

References 29 publications

Empirical evidence for large‐scale human impact on intertidal aggregations, larval supply and recruitment of Pyura praeputialis around the Bay of Antofagasta, Chile

Empirical evidence for large‐scale human impact on intertidal aggregations, larval supply and recruitment of Pyura praeputialis around the Bay of Antofagasta, Chile

Effects of inter-annual temperature variability, including ENSO and post-ENSO events, on reproductive traits in the tunicatePyura praeputialis

Ethical consideration in invasion ecology: A marine perspective

Contact Info

Product

Resources

About