Geographic position and landscape composition explain regional patterns of migrating landbird distributions during spring stopover along the northern coast of the Gulf of Mexico

AbstractThe strongest hurricanes over the North Atlantic Ocean are getting stronger, with the increase related to rising ocean temperature. Here, the authors develop a procedure for estimating future wind losses from hurricanes and apply it to Eglin Air Force Base along the northern coast of Florida. The method combines models of the statistical distributions for extreme wind speed and average sea surface temperature over the Gulf of Mexico with dynamical models for tropical cyclone wind fields and damage losses. Results show that the 1-in-100-yr hurricane from the twentieth century picked at random to occur in the year 2100 would result in wind damage that is 36% [(13%, 76%) = 90% confidence interval] greater solely as a consequence of the projected warmer waters in the Gulf of Mexico. The method can be applied elsewhere along the coast with modeling assumptions modified for regional conditions.

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Radiocarbon in otoliths of tropical marine fishes: Reference Δ14C chronology for north Caribbean waters

PLoS ONE ◽

10.1371/journal.pone.0251442 ◽

2021 ◽

Vol 16 (5) ◽

pp. e0251442

Author(s):

Virginia R. Shervette ◽

Katherine E. Overly ◽

Jesús M. Rivera Hernández

Keyword(s):

Gulf Of Mexico ◽

Validation Studies ◽

Reef Fishes ◽

Age Validation ◽

Regional Patterns ◽

Temporal Relationships ◽

Fish Samples ◽

Original Goal ◽

Reef Fish Species ◽

The Tropics

Reef fishes support important fisheries throughout the Caribbean, but a combination of factors in the tropics makes otolith microstructure difficult to interpret for age estimation. Therefore, validation of ageing methods, via application of Δ14C is a major research priority. Utilizing known-age otolith material from north Caribbean fishes, we determined that a distinct regional Δ14C chronology exists, differing from coral-based chronologies compiled for ageing validation from a wide-ranging area of the Atlantic and from an otolith-based chronology from the Gulf of Mexico. Our north Caribbean Δ14C chronology established a decline series with narrow prediction intervals that proved successful in ageing validation of three economically important reef fish species. In examining why our north Caribbean Δ14C chronology differed from some of the coral-based Δ14C data reported from the region, we determined differences among study objectives and research design impact Δ14C temporal relationships. This resulted in establishing the first of three important considerations relevant to applying Δ14C chronologies for ageing validation: 1) evaluation of the applicability of original goal/objectives and study design of potential Δ14C reference studies. Next, we determined differences between our Δ14C chronology and those from Florida and the Gulf of Mexico were explained by differences in regional patterns of oceanic upwelling, resulting in the second consideration for future validation work: 2) evaluation of the applicability of Δ14C reference data to the region/location where fish samples were obtained. Lastly, we emphasize the application of our north Caribbean Δ14C chronology should be limited to ageing validation studies of fishes from this region known to inhabit shallow water coral habitat as juveniles. Thus, we note the final consideration to strengthen findings of future age validation studies: 3) use of Δ14C analysis for age validation should be limited to species whose juvenile habitat is known to reflect the regional Δ14C reference chronology.

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Winds aloft over three water bodies influence spring stopover distributions of migrating birds along the Gulf of Mexico coast

The Auk ◽

10.1093/ornithology/ukab051 ◽

2021 ◽

Author(s):

Hannah L Clipp ◽

Jeffrey J Buler ◽

Jaclyn A Smolinsky ◽

Kyle G Horton ◽

Andrew Farnsworth ◽

...

Keyword(s):

Atlantic Ocean ◽

Gulf Of Mexico ◽

Caribbean Sea ◽

Radar Data ◽

Water Bodies ◽

Northern Gulf Of Mexico ◽

The Caribbean ◽

Migrating Birds ◽

Spring Stopover ◽

Mexico Coast

Abstract Migrating birds contend with dynamic wind conditions that ultimately influence most aspects of their migration, from broad-scale movements to individual decisions about where to rest and refuel. We used weather surveillance radar data to measure spring stopover distributions of northward migrating birds along the northern Gulf of Mexico coast and found a strong influence of winds over nonadjacent water bodies, the Caribbean Sea and Atlantic Ocean, along with the contiguous Gulf of Mexico. Specifically, we quantified the relative influence of meridional (north–south) and zonal (west–east) wind components over the 3 water bodies on weekly spring stopover densities along western, central, and eastern regions of the northern Gulf of Mexico coast. Winds over the Caribbean Sea and Atlantic Ocean were just as, or more, influential than winds over the Gulf of Mexico, with the highest stopover densities in the central and eastern regions of the coast following the fastest winds from the east over the Caribbean Sea. In contrast, stopover density along the western region of the coast was most influenced by winds over the Gulf of Mexico, with the highest densities following winds from the south. Our results elucidate the important role of wind conditions over multiple water bodies on region-wide stopover distributions and complement tracking data showing Nearctic–Neotropical birds flying nonstop from South America to the northern Gulf of Mexico coast. Smaller-bodied birds may be particularly sensitive to prevailing wind conditions during nonstop flights over water, with probable orientation and energetic consequences that shape subsequent terrestrial stopover distributions. In the future, the changing climate is likely to alter wind conditions associated with migration, so birds that employ nonstop over-water flight strategies may face growing challenges.

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Long-term Observations of Atmospheric Speciated Mercury at a Coastal Site in the Northern Gulf of Mexico during 2007–2018

10.5194/egusphere-egu2020-12156 ◽

2020 ◽

Author(s):

Xinrong Ren ◽

Winston Luke ◽

Paul Kelley ◽

Mark Cohen ◽

Mark Olson ◽

...

Keyword(s):

Seasonal Variation ◽

Gulf Of Mexico ◽

Wet Deposition ◽

Elemental Mercury ◽

Early Summer ◽

Atmospheric Mercury ◽

Photochemical Oxidation ◽

Mercury Species ◽

Monitoring Site ◽

Northern Coast

Atmospheric mercury species (including gaseous elemental mercury (GEM), gaseous oxidized mercury (GOM) and particulate-bound mercury (PBM)), trace pollutants (including O3, SO2, CO, NO, NOY and black carbon), and meteorological parameters have been continuously monitored since 2007 at an Atmospheric Mercury Network (AMNet) site located on the northern coast of the Gulf of Mexico at the Grand Bay National Estuarine Research Reserve (NERR) in Moss Point, Mississippi. For the data collected between 2007 and 2018, the average concentrations and standard deviations were 1.39 &#177; 0.22 ng m-3 for GEM, 5.1 &#177; 10.2 pg m-3 for GOM, 5.9 &#177; 13.0 pg m-3 for PBM, and 309 &#177; 407 ng m-2 wk-1 for mercury wet deposition, with interannual trends of -0.009 ng m-3 yr-1 for GEM, -0.36 pg m-3 yr-1 for GOM, 0.18 pg m-3 yr-1 for PBM, and 2.8 ng m-2 wk-1 yr-1 for mercury wet deposition. The trends are statistically significant for GEM and GOM, but not statistically significant for PBM and mercury wet deposition. Diurnal variation of GEM shows lower concentrations in the early morning due to GEM depletion likely due to plant uptake in high humidity events and slight elevation during the day likely due to downward mixing of higher concentrations of GEM in the air aloft to the surface. Seasonal variation of GEM shows higher levels in winter and spring and lower levels in summer and fall. Diurnal variations of both GOM and PBM show broad peaks in the afternoon likely due to photochemical oxidation of GEM. Seasonally, PBM measurements exhibit higher levels in winter and early spring and lower levels in summer, while GOM measurements show high levels in late spring/early summer and late fall and low levels in winter. The seasonal variation of mercury wet deposition shows higher values in summer and lower values in winter due to higher precipitation amounts in summer than in winter. As expected, anticorrelation between Hg wet deposition and the sum of GOM and PBM but positive correlation between Hg wet deposition and rainfall were observed. Correlation among GOM, ozone, and SO2 suggests two possible GOM sources: direct emissions and photochemical oxidation of GEM with the possible influence of boundary dynamics and seasonal variability. This study indicates that the monitoring site, which is located in a coastal environment of the Gulf of Mexico, might experience impacts from mercury sources that are both local and regional in nature.

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