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Genotype by environment interactions, heritabilities and genetic correlations for productive traits of Haliotis rufescens

Autores:

Farías, W., Winkler, F., & Brokordt, K.

Resumen:

A critical aspect of a selective breeding program is whether responses of traits of interest are similar in different environments. The magnitude of the genotype by environment interaction (GEI) together with heritability (h2) accounts for this aspect. Despite the economic significance of abalones and the interest in genetic improvement programs for their cultivation, only one previous study has reported GEI estimations for this group of mollusks. The objective of the present study was to estimate h2 and the existence of GEI for growth traits of Haliotis rufescens cultivated in Chilean farms with different environmental and management conditions. A total of 2 cohorts (2007 and 2009) of 50 and 42 families of full sibs (FS), respectively, were used. Replicates of each FS family of the 2007 cohort were distributed in two farms in the northern region of the country and were evaluated after 1 and 2 years of cultivation. For the 2009 cohort, replicates of each family were distributed in a farm in the northern region and a farm in the southern region of the country. The estimated h2 values were significant for all traits, with the length and width of the shell and total weight varying primarily by cohort between 0.22–0.62, 0.16–0.58 and 0.40–0.53, respectively. The genetic correlations (rG) between traits were all higher than 0.82. The expected correlated responses for improving the total weight using the shell length as a selection criterion predict a selection gain (14–51%) similar to what would be obtained by selecting directly for weight (16–51%) in all environments examined. Thus, indirect selection by shell length and the direct use of total weight as a selection criterion would yield similar effects in terms of the increase in weight. High rG, not significantly different from 1, were observed for the analyzed traits between replicates of the families in any of the farms compared, both within the northern region and between the northern and southern regions of the country. These high rG were indicative of non-significant GEI for the analyzed traits. Therefore, results suggest that one selective breeding program could provide improved red abalone for the industry in Chile with consistent results between farms located in different environments.

Año: 2017

Palabras claves: Abalone, Aquaculture, Breeding, Heritability, Genetic correlation, Genotype by environment interaction

Referencia APA: Farías, W., Winkler, F., & Brokordt, K. (2017). Genotype by environment interactions, heritabilities and genetic correlations for productive traits of Haliotis rufescens. Aquaculture, 473, 407-416. http://dx.doi.org/10.1016/j.aquaculture.2017.02.030

Co‐operation between large‐scale MPAs: successful experiences from the Pacific Ocean.

Autores:

Friedlander, A. M., Wagner, D., Gaymer, C. F., Wilhelm, T. A., Lewis, N. A., Brooke, S., Kikiloi, K. & Varmer, O.

Resumen:

Nations have recently committed to protecting 20–30% of the ocean at various global summits; however, marine protected areas currently cover <3% of the ocean. Large-scale marine protected areas (LSMPAs, >100 000 km2) are a new concept in global marine conservation that offer real hope in achieving global conservation targets.
Many of the existing LSMPAs are remote islands in the Pacific that share common natural history, threats, culture, as well as scientific and management needs.
As a result of their common ancestry, many Pacific cultures have a long history of collaboration, including sharing resources, information and expertise to ensure the long-term sustainability of their resources.
Management, governance and research capacity limitations are magnified in LSMPAs, therefore highlighting the need to return to these prior forms of collaboration to achieve conservation objectives.
Several LSMPAs in the Pacific have collaborated to achieve their management and scientific goals, including documented collaborations among the Papahānaumokuākea Marine National Monument, the Phoenix Islands Protected Area, the Pacific Remote Islands Marine National Monument, the Marianas Trench Marine National Monument, the Motu Motiru Hiva Marine Park, the Natural Park of the Coral Sea, and the Cook Islands Marine Park.
Collaborations among LSMPAs in the Pacific include bilateral agreements, learning exchanges, as well as research, monitoring and enforcement activities. By working together, Pacific LSMPAs have been able to overcome some of the management and scientific challenges associated with conserving vast areas of the oceans.

Año: 2016

Palabras claves:

Referencia APA: Friedlander, A. M., Wagner, D., Gaymer, C. F., Wilhelm, T. A., Lewis, N. A., Brooke, S., Kikiloi, K. & Varmer, O. (2016). Co‐operation between large‐scale MPAs: successful experiences from the Pacific Ocean. Aquatic Conservation: Marine and Freshwater Ecosystems, 26(S2), 126-141.

Life history patterns are correlated with predictable fluctuations in highly seasonal environments of semi-terrestrial burrowing crayfish.

Autores:

Palaoro, A., del Valle, E., & Thiel, M.

Resumen:

Animals living in extreme environments with predictable seasonality may have important life history events correlated to favourable periods. These animals pass critical life stages in protected habitats, especially during early life, often receiving parental care. It is thus hypothesized that juveniles rely on protective microhabitats provided by their parents, becoming independent only during favourable seasons. Semi-terrestrial crayfish Parastacus pugnax inhabit burrows in highly seasonal and predictable environments, thus being well suited to test this hypothesis. Following marked burrows and individual crayfish we examined the life history patterns of P. pugnax in their natural environment to test the predictions that (i) burrowing activity is higher during the wet season, (ii) reproductive events occur during favourable seasons and (iii) juveniles only disperse after reaching larger sizes. There was little or no burrowing activity during the dry season, when soil was more compact, but burrows became wider and had more openings during the wet season. After hatching, juveniles cohabited with adults for at least 4 months during the dry season. During this period juveniles grew considerably, starting independent lives during the wet season. These results suggest that the prolonged parent-offspring cohabitation evolved in response to the predictable seasonal variations in the crayfish habitat.

Año: 2016

Palabras claves: Behavioural adaptations, Fossorial species, Parastacus pugnax, Parental care, Seasonality.

Referencia APA: Palaoro, A., del Valle, E., & Thiel, M. (2016). Life history patterns are correlated with predictable fluctuations in highly seasonal environments of semi-terrestrial burrowing crayfish. Hydrobiologia, 767(1), 51-63.

No sex-related dispersal limitation in a dioecious, oceanic long-distance traveller: the bull kelp Durvillaea antarctica.

Autores:

Lizée-Prynne, D., López, B., Tala, F., & Thiel, M.

Resumen:

Dispersal of dioecious floating seaweeds could be limited due to biological constraints. This study examined for benthic and floating populations (stranded individuals) of the rafting kelp Durvillaea antarctica whether male and female individuals cohabit within one holdfast. As a previous study had indicated colour differences between sexes, we also examined whether these colour differences are consistent and possibly related to pigment and phlorotannin concentrations. Our large-scale survey of rafted holdfasts and a small-scale survey of benthic holdfasts at two sites found that reproductive males and females do travel together in coalesced holdfasts, although this proportion is relatively low (5–17%). There were no sex-specific differences in pigment and phlorotannin concentrations, but there were significant differences between the two benthic populations. There was no relationship between the colouration of thalli and the concentration of pigments but there was a slight colour difference between vegetative and reproductive sexual stages. Based on these results we conclude that biological conditions are not the cause for the lack of genetic connectivity between D. antarctica populations from central Chile. Instead, we suggest that ecological processes, such as density-blocking and physical factors (i.e. currents and winds), limit the potential for successful rafting dispersal.

Año: 2016

Palabras claves: Chemical composition; dioecious seaweeds; dispersal potential; phlorotannins; pigments; rafting.

Referencia APA: Lizée-Prynne, D., López, B., Tala, F., & Thiel, M. (2016). No sex-related dispersal limitation in a dioecious, oceanic long-distance traveller: the bull kelp Durvillaea antarctica. Botanica Marina, 59(1).

Short- and long-term acclimation patterns of the giant kelp Macrocystis pyrifera(Laminariales, Phaeophyceae) along a depth gradient.

Autores:

Koch, K., Thiel, M., Hagen, W., Graeve, M., Gómez, I., & Jofre, D. et al.

Resumen:

The giant kelp, Macrocystis pyrifera, is exposed to highly variable irradiance and temperature regimes across its geographic and vertical depth gradients. The objective of this study was to extend our understanding of algal acclimation strategies on different temporal scales to those varying abiotic conditions at various water depths. Different acclimation strategies to various water depths (0.2 and 4 m) between different sampling times (Jan/Feb and Aug/Sept 2012; long-term acclimation) and more rapid adjustments to different depths (0.2, 2 and 4 m; short-term acclimation) during 14 d of transplantation were found. Adjustments of variable Chl a fluorescence, pigment composition (Chl c, fucoxanthin), and the de-epoxidation state of the xanthophyll cycle pigments were responsible for the development of different physiological states with respect to various solar radiation and temperature climates. Interestingly, the results indicated that phlorotannins are important during long-term acclimation while antioxidants have a crucial role during short-term acclimation. Furthermore, the results suggested that modifications in total lipids and fatty acid compositions apparently also might play a role in depth acclimation. In Aug/Sept (austral winter), M. pyrifera responded to the transplantation from 4 m to 0.2 m depth with a rise in the degree of saturation and a switch from shorter- to longer-chain fatty acids. These changes seem to be essential for the readjustment of thylakoid membranes and might, thus, facilitate efficient photosynthesis under changing irradiances and temperatures. Further experiments are needed to disentangle the relative contribution of solar radiation, temperature and also other abiotic parameters in the observed physiological changes.

Año: 2016

Palabras claves: Acclimation; antioxidants; Chile; fatty acid composition; PAR ; phlorotannins; temperature; total lipids.

Referencia APA: Koch, K., Thiel, M., Hagen, W., Graeve, M., Gómez, I., & Jofre, D. et al. (2016). Short -and long- term acclimation patterns of the giant kelp Macrocystis pyrifera (Laminariales, Phaeophyceae) along a depth gradient. Journal Of Phycology, 52(2), 260-273.

A rose by any other name: systematics and diversity in the Chilean giant barnacle Austromegabalanus psittacus (Molina, 1782) (Cirripedia).

Autores:

Pappalardo, P., Pitombo, F., Wares, J., & Haye, P.

Resumen:

We analyzed the population structure of the edible barnacle Austromegabalanus psittacus (Molina, 1782) along most of the coast of Chile. The analysis of population structure was based on nucleotide sequences of the mitochondrial cytochrome oxidase I (COI) gene region. We also tested for differences between the regions to the north and south of 30-33°S, as these latitudes represent a recognized biogeographic break and important oceanographic transitions occur in that area. No geographic differentiation was evident when using Hudson’s nearest-neighbor (S nn) statistic to analyze genetic differences between all populations. F st values nevertheless showed overall genetic structure among sites. Significant geographic structure was found using S nn and analysis of molecular variance (AMOVA) when locations were separated into northern and southern regions, with a stronger signal when the geographic division is set at 33°S. Our results support the idea that oceanographic transitions can affect the genetic structure in species with pelagic larvae. We also discuss observations on size structure differences within the natural range of A. psittacus and this barnacle’s sympatric occurrence with another barnacle, Megabalanus concinnus (Darwin, 1854) in its northern range.

Año: 2016

Palabras claves: Genetic diversity; genetic structure; picoroco; phylogeography; larval dispersal.

Referencia APA: Pappalardo, P., Pitombo, F., Wares, J., & Haye, P. (2016). A rose by any other name: systematics and diversity in the Chilean giant barnacle Austromegabalanus psittacus (Molina, 1782) (Cirripedia). Journal Of Crustacean Biology, 36(2), 180-188.

Vertical distribution of rocky subtidal assemblages along the exposed coast of north-central Chile.

Autores:

Stotz, W., Aburto, J., Caillaux, L., & González, S.

Resumen:

Through a systematic study of a stretch of coast in north central Chile, the variety and vertical zonation patterns of the rocky subtidal communities are described, thereby revising apparent uniformity and lack of vertical zonation of the rocky subtidal of southeastern Pacific shores previously reported in the literature. Over the 600 km of coast studied, the following pattern of depth-zonation is described: an upper fringe (lower part of the sublittoral fringe) characterized by barren grounds dominated by calcareous encrusting algae and the sea urchin Tetrapygus niger; an intermediate fringe (upper Infralittoral sub-zone) characterized either by deep barren grounds similar to the former, or kelp beds of Lessonia trabeculata, or an assemblage of suspension feeding organisms, as the big barnacle Austromegabalanus psittacus and/or the tunicate Pyura chilensis; and a deep fringe (Circalittoral sub-zone) dominated by small encrusting or mobile invertebrates. This basic vertical zonation pattern of the shallow rocky subtidal communities seems to be common to most of the temperate coasts of the world. The analysis, first of the occurrence of the general zonation pattern and second of the species composition within the assemblages corresponding to each sub-zone, offers a useful framework for the assessment of the eventual impacts and changes within the shallow rocky subtidal habitat, for example within environmental monitoring programs.

Año: 2016

Palabras claves: Chile; Community monitoring; Southeastern Pacific; Subtidal; Zonation pattern.

Referencia APA: Stotz, W., Aburto, J., Caillaux, L., & González, S. (2016). Vertical distribution of rocky subtidal assemblages along the exposed coast of north-central Chile. Journal Of Sea Research, 107, 34-47.

Mating rock shrimp hedge their bets: old males take greater risk, but only after careful assessment of the investment scenario.

Autores:

Ory, N., van Son, T., & Thiel, M.

Resumen:

Mature organisms often have to trade reproductive opportunities against the need to survive, especially in species with exaggerated, sexually selected traits. Life history theory predicts that old males with low residual reproductive value (RRV) would accept greater risk for current reproduction than their younger counterparts. Accordingly, we tested the prediction that, under predation risk, old males of the rock shrimp Rhynchocinetes typus pair with females faster and for a longer time than young males do. We exposed young and old dominant males (in the final ontogenetic stage, called “robustus”) to a female in the absence and presence of a predator. As predicted, older robustus males modified their mating behavior when exposed to a predator. However, in contrast to the prediction, they delayed female seizure under predation risk, possibly to carefully assess the actual threat before initiating female guarding. Once they had established the mate-guarding position, old robustus males did not interrupt it until the end of female spawning and, in the presence of predators, even guarded the female significantly longer than in predator-free treatments. In contrast, younger robustus males did not delay female seizure but abandoned the female repeatedly when a predator was present, suggesting that they perceived and responded to the predation risk. Our results suggest that older robustus males have the experience to assess threats before engaging in risky behaviors that bolster their reproductive success. Although consistent with the theory that low RRV individuals should accept greater reproductive risk, we suggest that old individuals do not recklessly engage in risky behaviors but rather cautiously evaluate the threats before investing in a potentially terminal reproductive event.

Año: 2015

Palabras claves: AgeMate-guarding, Mating behavior,Predation risk,Residual reproductive value,Risk-taking strategies.

Referencia APA: Ory, N., van Son, T., & Thiel, M. (2015). Mating rock shrimp hedge their bets: old males take greater risk, but only after careful assessment of the investment scenario. Behavioral Ecology And Sociobiology, 69(12), 1975-1984.

Numbers and sizes of the shrimp Rhynchocinetes uritaiKubo, 1942 (Decapoda: Caridea) caught in bait and refuge traps.

Autores:

Osawa, Y., Bauer, R., Aoki, M., & Thiel, M.

Resumen:

Catch rates and sizes of hingebeak shrimp Rhynchocinetes uritaiKubo, 1942 were studied with two types of traps: bait traps that were exposed for 1-2 days and unbaited “refuge traps” exposed for 2-4 weeks. Shrimp were collected twice a month from June 2010 to May 2012 on rocky substrata in Oura Bay, Shimoda, Japan. Overall the numbers of shrimp caught did not differ between the two trap types, but when adjusted for soak times, the bait traps had substantially higher catch rates than the refuge traps. Addition of light to the bait traps had no significant effect on catch rates. However, shrimp in the baited traps were significantly larger than those in the refuge traps. The results show that size distribution can be greatly affected by trap type. Consequently, using two types of traps simultaneously increases not only the catch efficiency but also ensures that all sizes of the reproductively mature shrimp population are sampled in adequate numbers, which is especially important in protandric hermaphrodites.

Año: 2015

Palabras claves: Hingebeak shrimp; bait traps; catch efficiency; refuge traps.

Referencia APA: Osawa, Y., Bauer, R., Aoki, M., & Thiel, M. (2015). Numbers and sizes of the shrimp Rhynchocinetes uritai Kubo, 1942 (Decapoda: Caridea) caught in bait and refuge traps. Journal Of Crustacean Biology, 35(6), 768-775

First record of the sea anemone Diadumene lineata (Verrill, 1869)from the Chilean coast.

Autores:

Häussermann, V., Spano, C., Thiel, M., & Lohrmann, K.B.

Resumen:

The orange-striped green sea anemone Diadumene lineata (Verrill 1871) was originally described from Japan but has been recorded as an invasive species from temperate and tropical coasts all over the world, being presumably transported on ship hulls or with seafood shipments. Here, we report the occurrence of this species for the first time from the South East Pacific, specifically on the coast of Coquimbo, northern Chile. Two specimens were spotted in 2012 and approximately 15 individuals were collected and examined in 2014. Most specimens were identified both externally and internally, confirming the cnidome described for the species in several individuals. Generally, the greenish-brown specimens had a pedal disc diameter of up to 7 mm and possessed between 2 and 11 irregularly distributedorange stripes. Since D. lineata is known to proliferate quickly, it is strongly recommended to start monitoring the area for possible outbreaks.

Año: 2015

Palabras claves:

Referencia APA: Häussermann, V., Spano, C., Thiel, M., & Lohrmann, K.B. (2015). First record of the sea anemone Diadumene lineata (Verrill, 1869) from the Chilean coast. In Spixiana, Zeitschrift Für Zoologie. Editor Gerhard Haszprunar. Bavarian State Collection Of Zoology (zoologische Staatssammlung München). pp. 39-42.

Genetic diversity in Chilean populations of rainbow trout, Oncorhynchus mykiss.

Autores:

Carcamo, C., Diaz, N., & Winkler, F.

Resumen:

The rainbow trout Oncorhynchus mykiss, was first introduced in Chile between 1905 and 1920 and is currently widely distributed in Chile from Antofagasta (23°S) to Patagonia (55ºS). The broad range of the geographic and climatic distributions of this species in Chile offers a unique opportunity to study the effect of naturalization of an introduced species on its genetic variability. It is of particular importance to observe the genetic variability of populations in the northern range of this species distribution, in a transition zone where a Mediterranean-type climate changes to an arid climate. The present study analyzed allozymic variability and distribution within and between populations of O. mykiss from the river basins of Elqui and Limarí rivers, and six culture strains, using starch-gel protein electrophoresis. Populations were found to be in Hardy-Weinberg equilibrium and the average values of He (0.045), polymorphism (13.9%) and allele per locus (1.19) are similar to rainbow trout in its native distributional range. About 77.8% of the genetic variability was within population, similar to the variability reported for wild populations in the northern hemisphere. However, a marked genetic differentiation between wild populations was also found. This is likely to be the consequence of initial founder effects followed by subsequent introgression of resident populations caused by reseeding with trout of different origins in both basins.

Año: 2015

Palabras claves: Oncorhynchus mykiss, rainbow trout, Salmonidae, genetic variation, aquaculture, conservation.

Referencia APA: Carcamo, C., Diaz, N., & Winkler, F. (2015). Genetic diversity in Chilean populations of rainbow trout, Oncorhynchus mykiss. Latin American Journal Of Aquatic Research, 43(1), 59-70.

Management of marine resources through a local governance perspective: Re-implementation of traditions for marine resource recovery on Easter Island.

Autores:

Aburto, J., Gaymer, C., Haoa, S., & González, L.

Resumen:

Easter Island (Rapa Nui) is one of the most isolated places in the world. The local Rapanui people have noticed an extreme decline in marine resources, which is due to the exploitation of these resources. Top-down regulations (e.g. fisherman and boat registrations and restrictions on catch-length and fishing season and location) implemented by the central fishery authorities located ∼4000 km from the island do not represent the cultural heritage and interests of the Rapanui people. According to the local people, one of the traditional ways to protect marine resources was the taboo (or tapu in Rapa Nui) that regulated the fish harvest. Key informants were interviewed to assess what they knew about the tapu in fisheries and so that the feasibility of its implementation could be assessed based on current local conditions. The tapu that had the greatest potential impact on regulating open water resources, especially tuna, was the traditional belief that consumption of open-water fish during winter months would cause asthma. According to the interviewees, the real reason for this tapu was to protect the fish during its reproductive period, and the asthma threat was only a way to enforce the restriction. At present, tapu is not respected because of the high economic activity related to the tourism that demands fish like tuna all year. Even though many Rapanui people agree that tapu re-implementation would be the best alternative to recover marine resources, people also think it is difficult to implement under modern conditions. We propose to promote a participatory process for development of a local governance structure that will use local traditions and beliefs, including tapu, to support the local decision-making process for reverting the decline of marine resources.

Año: 2015

Palabras claves: Easter Island; Resource management; TEK; Taboo; Local governance.

Referencia APA: Aburto, J., Gaymer, C., Haoa, S., & González, L. (2015). Management of marine resources through a local governance perspective: Re-implementation of traditions for marine resource recovery on Easter Island. Ocean & Coastal Management, 116, 108-115.