Alma Paola Rodríguez-Troncoso

Differences in Growth and Calcification Rates in the Reef-Building Coral Porites lobata: The Implications of Morphotype and Gender on Coral Growth

Corals display different growth forms as an adaptive response to both local and global environmental conditions. Despite the importance of morphologic variability on corals, growth and calcification rates of different coral morphotypes have been poorly recorded in the Eastern Pacific. The purpose of this study was to compare annual extension rate (cm yr-1), skeletal density (g cm-3), calcification rate (g cm-2 yr-1) and tissue thickness (mm) of males and females colonies in three different morphotypes of the common reef-building coral Porites lobata; columnar, massive, and free-living (corallith) forms. The results show significant differences in all 4-growth parameters between morphotypes over a 6-year interval, and also differences between males and females in most morphotypes. Massive colonies presented 15-33% faster annual rates compared with columnar and free-living. Male colonies showed 30-40% faster annual rates than females for both columnar and corallith morphologies. These data exhibit the extensive plasticity of this species and highlight the fact that each morphotype x gender group produced a different physiological response to environmental conditions. Therefore, these information reveal that P. lobata from the Eastern Tropical Pacific develops different morphologies to allow it to maintain coral species population, characteristics that enhance the species possibility to further its distribution across the reef-framework

Calcification and growth rate recovery of the reef-building Pocillopora species in the northeast tropical Pacific following an ENSO disturbance

Pocilloporids are one of the major reef-building corals in the eastern tropical Pacific (ETP) and also the most affected by thermal stress events, mainly those associated with El Niño/Southern Oscillation (ENSO) periods. To date, coral growth parameters have been poorly reported in Pocillopora species in the northeastern region of the tropical Pacific. Monthly and annual growth rates of the three most abundant morphospecies (P. cf. verrucosa, P. cf. capitata, and P. cf. damicornis) were evaluated during two annual periods at a site on the Pacific coast of Mexico. The first annual period, 2010–2011 was considered a strong ENSO/La Niña period with cool sea surface temperatures, then followed by a non-ENSO period in 2012–2013. The linear extension rate, skeletal density, and calcification rate averaged (±SD) were 2.31 ± 0.11 cm yr−1, 1.65 ± 0.18 g cm−3, 5.03 ± 0.84 g cm−2 yr-1 respectively, during the strong ENSO event. In contrast, the respective non-ENSO values were 3.50 ± 0.64 cm yr−1, 1.70 ± 0.18 g cm−3, and 6.02 ± 1.36 g cm−2 yr−1. This corresponds to 52% and 20% faster linear extension and calcification rates, respectively, during non-ENSO period. The evidence suggests that Pocillopora branching species responded positively with faster growth rates following thermal anomalies, which allow them to maintain coral communities in the region.

Abundance of three species of Isopoda (Peracarida, Isopoda) associated with a coral reef environment in Pacific Mexico

Fragments of dead coral belonging to Pocillopora Lamarck, 1816 were used during a 1-year period as artificial micro-habitats and positioned at a coral reef community at Islas Marietas, Bahia Banderas, on the west coast of Mexico, to attract and capture isopods. Three species of isopods, totaling 961 specimens were collected. The dominant species was Joeropsis dubia (Menzies, 1951) (Joeropsididae) (83.03% of the total number of specimens), followed by Califanthura squamosissima (Menzies, 1951) (Paranthuridae) (9.78%), and Paracerceis sculpta (Holmes, 1904) (Sphaeromatidae) (7.18%). The average density of isopods was of 12.0 × 10−2 ind. ⋅ cm−2. A positive relationship between water temperature and total density of individuals during the sampling period was found. Annual water temperature changes influenced the abundance of each species in a similar way, with the higher abundances associated to the lower temperatures, which is also related to an increase in primary productivity and the presence of upwellings in the area.

Structural and environmental effects on an assemblage of echinoderms associated with a coral community

Echinoderms are a conspicuous assemblage associated with coral communities, which provides them with food, shelter, and nursery areas. Temporal and spatial changes in environmental conditions may modify their density and composition, which furthermore may affect the structure of the coral community. In order to identify the response of echinoderm composition to environmental fluctuations, variations in the density were evaluated at spatial and temporal levels from 2011–2014 in Islas Marietas National Park, a National Protected Area located off the Mexican Pacific coast, which harbors the most important coral and echinoderm community in the region. The results showed that the species Diadema mexicanum, Centrostephanus coronatus, and Eucidaris thouarsii, were dominant. Differences between areas off the islands were observed, as Isla Redonda showed the highest values (1.31 ± 0.15 in. m2, S¯

Bacterial assemblages associated with coral species of the Mexican Central Pacific

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New records of sea cucumbers (Echinodermata: Holothuroidea) at Islas Marietas, Central Mexican Pacific

= 7.74 ± 0.17) associated with high heterogeneity and availability of food resources. Isla Larga had the lowest density (0.89 ± 0.7 in. m2) and richness (S¯

The effects of an abnormal decrease in temperature on the Eastern Pacific reef-building coral Pocillopora verrucosa

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