AGU 2018 Poster: Long-Term Recovery of Life in the Chicxulub Crater

At the end of the Cretaceous Period (66 Ma), the impact of a meteorite on the Yucatán platform in the southern Gulf of Mexico caused the extinction of 75% of species on Earth, including 90% of planktic microorganisms like foraminifera and calcareous nannoplankton. As the ocean ecosystem struggled to get back on its feet after this calamity, the recovery of marine primary productivity was geographically heterogeneous. Some authors had speculated that this heterogeneity was driven by the uneven distribution of toxic metals in the ocean, and was directly related to distance from the Chicxulub crater. However, results from recent International Ocean Discovery Program/International Continental Drilling Program (IODP/ICDP) joint Expedition 364, which drilled the Chicxulub crater itself, found evidence of the rapid establishment of a healthy, high-productivity ecosystem in the crater within 30 kyr of the impact. This result suggests that the recovery of marine productivity is likely driven by ecological factors like incumbency and competitive exclusion. However, it also raises several additional questions: How long does high productivity last in the crater? Is this high productivity driven by the impact-generated hydrothermal system or is it a Gulf-wide phenomenon? If so, what’s driving it?Here, we examine planktic and benthic foraminifera, calcareous nannoplankton, major, minor, and trace elements, and stable isotopes from the Paleocene interval of IODP Site M0077 in the Chicxulub Crater, and compare it to publically available planktic foraminifer and nannoplankton counts from three oil wells in the northern Gulf of Mexico to determine the long term trends in productivity in the Chicxulub Crater and whether or not they are limited to the crater or extend across the Gulf. We show that the first ~million years of the Paleocene are characterized by a eutrophic surface waters that slowly transition to mesotrophic and then oligotrophic by the middle Paleocene. Foraminiferal data from the northern Gulf of Mexico demonstrates that this trend is regional.

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Assessing the impact of oil-related activities on benthic macroinfauna assemblages of the Campeche shelf, southern Gulf of Mexico

Marine Ecology Progress Series ◽

10.3354/meps289089 ◽

2005 ◽

Vol 289 ◽

pp. 89-107 ◽

Cited By ~ 23

Author(s):

HA Hernández Arana ◽

RM Warwick ◽

MJ Attrill ◽

AA Rowden ◽

G Gold-Bouchot

Keyword(s):

Gulf Of Mexico ◽

Southern Gulf Of Mexico ◽

The Impact

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Long-term change in the abundances of northern Gulf of Mexico scyphomedusae Chrysaora sp. and Aurelia spp. with links to climate variability

Limnology and Oceanography ◽

10.4319/lo.2013.58.1.0235 ◽

2012 ◽

Vol 58 (1) ◽

pp. 235-253 ◽

Cited By ~ 30

Author(s):

Kelly L. Robinson ◽

William M. Graham

Keyword(s):

Climate Variability ◽

Gulf Of Mexico ◽

Northern Gulf Of Mexico ◽

Term Change

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Diversity of mangrove root-dwelling sponges in a tropical coastal ecosystem in the southern Gulf of Mexico region

Helgoland Marine Research ◽

10.1186/s10152-020-00545-6 ◽

2020 ◽

Vol 74 (1) ◽

Author(s):

Pedro de Jesús Castellanos-Pérez ◽

Laura Elena Vázquez-Maldonado ◽

Enrique Ávila ◽

José Antonio Cruz-Barraza ◽

Julio César Canales-Delgadillo

Keyword(s):

Gulf Of Mexico ◽

New Records ◽

Coastal Ecosystem ◽

High Productivity ◽

Mangrove Root ◽

Red Mangrove ◽

Reef Environments ◽

Southern Gulf Of Mexico ◽

The Caribbean ◽

Central Atlantic

AbstractSponges are one of the most conspicuous groups of epibionts in mangrove prop root habitats. However, with the exception of the Caribbean and the Indo-Pacific regions, studies focused on species diversity are lacking in other locations that have high mangrove coverage and are relatively distant from coral reef environments. Because mangrove-root epibiont communities, in general, have been understudied worldwide, this research contributes to filling this knowledge gap. In this study, a total of 30 sponge species (belonging to three subclasses, 14 families and 19 genera) were recorded as epibionts on prop roots of the red mangrove Rhizophora mangle in a tropical coastal ecosystem of the Southern Gulf of Mexico. Of these, five were new records for the Gulf of Mexico, 14 were new for the Mexican coasts of the gulf and 25 were new for the study area. Moreover, a similarity analysis based on presence/absence data of mangrove-associated sponges reported throughout the Western Central Atlantic region revealed that the sponge assemblage from the study area was more similar to those documented in most of the Caribbean locations (Jamaica, Cuba, Martinique, Panama, Venezuela, Belize and Colombia) rather than with those of the Northeast of the Gulf of Mexico, Guadeloupe and Trinidad. This relative intra-regional dissimilarity in the structure of mangrove-associated sponge assemblages may be related to differences in environmental conditions as well as taxonomic effort. The study area, unlike most of the Caribbean locations, is characterized by estuarine conditions and high productivity throughout the year. The inter-site variability recorded in the composition of mangrove-associated sponges was influenced by a set of factors such as salinity, dissolved oxygen and hydrodynamism. This study shows the importance of exploring the mangrove-associated sponge assemblages from different regions of the world as it furthers knowledge of the biodiversity and global distribution of this group.

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Extensive reproductive disruption, ovarian masculinization and aromatase suppression in Atlantic croaker in the northern Gulf of Mexico hypoxic zone

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2011.0529 ◽

2011 ◽

Vol 279 (1726) ◽

pp. 28-38 ◽

Cited By ~ 59

Author(s):

Peter Thomas ◽

Md. Saydur Rahman

Keyword(s):

Gulf Of Mexico ◽

Mississippi River ◽

Aromatase Activity ◽

Northern Gulf Of Mexico ◽

Hypoxia Exposure ◽

Hypoxic Zone ◽

Seasonal Hypoxia ◽

Reproductive Disruptions ◽

Reproductive Disruption

The long-term impacts on marine ecosystems of the recent dramatic worldwide increase in the incidence of coastal hypoxia are unknown. Here, we show widespread reproductive disruption in Atlantic croakers collected from hypoxic sites approximately 120 km apart in the extensive northern Gulf of Mexico continental shelf hypoxic zone. Gonadal growth and gamete production were impaired in croakers from hypoxic sites compared with fish from reference normoxic sites east of the Mississippi River Delta. Male germ cells were detected in approximately 19 per cent of croaker ovaries collected in the hypoxic region, but were absent in ovaries from normoxic sites. In addition, the sex ratio was skewed towards males at the hypoxic sites. The masculinization and other reproductive disruptions were associated with declines in neuroendocrine function, as well as ovarian and brain expression of aromatase (the enzyme that converts androgens to oestrogens). A similar incidence of ovarian masculinization and decline in ovarian aromatase expression were observed in croaker after chronic laboratory hypoxia exposure, indicating that ovarian masculinization is a specific hypoxia response and is due to decreased aromatase activity. The results suggest severe reproductive impairment can occur over large coastal regions in marine fish populations exposed to seasonal hypoxia, with potential long-term impacts on population abundance.

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