Fish eggs and larvae assemblages collected before and after the Deepwater Horizon oil spill, near Dauphin Island, Alabama, June-July 2007, 2008, 2009, 2010
Funded By:
Gulf of Mexico Research Initiative
Funding Cycle:
The Alabama Marine Environmental Science Consortium (MESC)
Research Group:
An Examination of Pre- and Post-Spill Ichthyoplankton Assemblage Dynamics
Frank Hernandez
University of Southern Mississippi / Department of Coastal Sciences
frank.hernandez@usm.edu
ichthyoplankton, larval fish, fish eggs, neuston, Fisheries Oceanography of Coastal Alabama, FOCAL
Abstract:
The goal of this project was to compare fish egg and larvae assemblages before and after the Deepwater Horizon oil spill to quantify potential impacts of the oil spill on these highly vulnerable early life stages. Depth-discrete and surface ichthyoplankton samples collected off coastal Alabama(20m depth) were available from a monitoring program that began in 2004 and continued through 2010. In this study, only samples collected during one month (June or July) coincident with the occurrence of oil at the study location were processed for egg and larvae identification and enumeration. Fish eggs and challenging larvae were identified to species level using DNA barcoding techniques (DNA sequencing of partial cytochrome c oxidase I [COI]). Remaining larvae were identified using described morphometric characters. Species abundances, vertical distributions, and assemblage metrics (e.g., richness, diversity) were compared before and after the oil spill to assess potential impacts of the oil spill on these early life stages of fishes. Ichthyoplankton data are from June and July sampling events in 2007, 2009 and 2010. Fish egg data are from 2007, 2008 and 2010..
Suggested Citation:
Frank Hernandez, Keith Bayha. 2015. Fish eggs and larvae assemblages collected before and after the Deepwater Horizon oil spill, near Dauphin Island, Alabama, June-July 2007, 2008, 2009, 2010. Distributed by: GRIIDC, Harte Research Institute, Texas A&M University–Corpus Christi. doi:10.7266/N7RN35TR
Purpose:
These data are a subset of the Fisheries Oceanography of Coastal Alabama (FOCAL) ichthyoplankton survey data relevant to the examination of Deepwater Horizon impacts on larval fish assemblages in the northern Gulf of Mexico. Fish egg identifications are also included to identify 'at risk' taxa spawning during the oil spill period (May-August).
Data Parameters and Units:
1. MININESS_Fish_eggs Contains fish egg counts and densities from MININESS tows Date Sampling date cruise Cruise ID (ship-month-year) station Sampling station mininess_id Unique ID given to entire MININESS tow net Individual net (nested within MININESS ID) mesh Mesh size in microns depth_bin Depth bin that the given net sampled preserve Chemical preservative used sampleid Unique ID given to the preserved contents of a single net comment Comments from the field sampling total_swept_volume Volume of water passed through the net (from flow meter) total_distance Distance net was towed (from flow meter) total_time_open Total time the net was deployed and actively sampling Eggs Number of fish eggs counted in the subsample Eggs Aliquot Fraction of sample used to count eggs (1=entire sample; 0.5=half sample) Remarks Comments from the laboratory processing of samples Total fish eggs Total fish eggs in the whole sample (calculated from egg count and aliquot, and then multipled by two because sample was split prior to counting) Egg density (no/m3) Total fish eggs divided by total swept volume Depth_max Maximum depth the net was towed for oblique tows only Areal egg density (no/m2) Areal density calculated for oblique tows only (count*(depth max/total swept volume)) 2. MININESS_5mm-_Fish Contains larval fish (less than 5mm) counts and densities from MININESS tows Date Sampling date cruise Cruise ID (ship-month-year) station Sampling station mininess_id Unique ID given to entire MININESS tow net Individual net (nested within MININESS ID) mesh Mesh size in microns depth_bin Depth bin that the given net sampled preserve Chemical preservative used dbo_mininess_header.comment Comments from the field sampling sampleid Unique ID given to the preserved contents of a single net total_swept_volume Volume of water passed through the net (from flow meter) total_distance Distance net was towed (from flow meter) total_time_open Total time the net was deployed and actively sampling Order_field Order-level fish ID Family Family-level fish ID Taxon Lowest-taxonomic-level fish ID dbo_ichthyoplankton_revised.comment Comments from the laboratory processing of samples Aliquot Fraction of sample used to count and ID larval fish (1=entire sample; 0.5=half sample) Measured Number of larval fish measured Not_Measured Number of larval fish not measured Total Total number of larval fish counted in the subsample Corrected_total Total fish larvae in the whole sample (calculated from fish count and aliquot, and then multipled by two because sample was split prior to counting) Density_fish_100m-3 Total fish larvae divided by total swept volume (then multiplied by 100) Depth_max Maximum depth the net was towed for oblique tows only Areal_density(fish/10m2) Areal density calculated for oblique tows only (count*(depth max/total swept volume)*10) 3. MININESS_5mm+_Fish Contains fish (greater than 5mm) counts and densities from MININESS tows Date Sampling date cruise Cruise ID (ship-month-year) station Sampling station mininess_id Unique ID given to entire MININESS tow net Individual net (nested within MININESS ID) mesh Mesh size in microns depth_bin Depth bin that the given net sampled preserve Chemical preservative used sampleid Unique ID given to the preserved contents of a single net dbo_mininess_header.comment Comments from the field sampling total_swept_volume Volume of water passed through the net (from flow meter)total_distance Distance net was towed (from flow meter) total_time_open Total time the net was deployed and actively sampling Order_field Order-level fish ID Family Family-level fish ID Taxon Lowest-taxonomic-level fish ID dbo_ichthyoplankton_5mm_header.comment Comments from the laboratory processing of samples Measured Number of fish measured Not_Measured Number of fish not measured Total Total number of fish counted in the subsample (no aliquots are used for greater than 5mm, all fish are counted) Density_fish_100m-3 Total fish divided by total swept volume (then multiplied by 100) Depth_max Maximum depth the net was towed for oblique tows only Areal_density(fish/10m2) Areal density calculated for oblique tows only (count*(depth max/total swept volume)*10) 4. MININESS_5mm-_Fish_lengths Contains larval fish (less than 5mm) counts and body lengths from MININESS tows Date Sampling date cruise Cruise ID (ship-month-year) station Sampling station mininess_id Unique ID given to entire MININESS tow net Individual net (nested within MININESS ID) mesh Mesh size in microns depth_bin Depth bin that the given net sampled preserve Chemical preservative used sampleid Unique ID given to the preserved contents of a single net dbo_mininess_header.comment Comments from the field sampling Taxon Lowest-taxonomic-level fish ID dbo_ichthyoplankton_revised.comment Comments from the laboratory processing of samples Aliquot Fraction of sample used to count and ID larval fish (1=entire sample; 0.5=half sample) Measured Number of larval fish measured Not_Measured Number of larval fish not measured Total Total number of larval fish counted in the subsample Corrected_total Total fish larvae in the whole sample (calculated from fish count and aliquot, and then multipled by two because sample was split prior to counting) L[number] Notochord/standard length in mm of fish [number] 5. MININESS_5mm+_Fish_lengths Contains fish (greater than 5mm) counts and body lengths from MININESS tows Date Sampling date cruise Cruise ID (ship-month-year) station Sampling station mininess_id Unique ID given to entire MININESS tow net Individual net (nested within MININESS ID) mesh Mesh size in microns depth_bin Depth bin that the given net sampled preserve Chemical preservative used sampleid Unique ID given to the preserved contents of a single net dbo_mininess_header.comment Comments from the field sampling order_field Order-level fish ID family Family-level fish ID Taxon Lowest-taxonomic-level fish ID dbo_ichthyoplankton_5mm_header.comment Comments from the laboratory processing of samples Measured Number of fish measured Not_Measured Number of fish not measured Total Total number of fish counted in the sample (greater than 5mm fish are not subsampled) length Notochord/standard length in mm of fish (each fish is listed in a separate row) 6. Neuston_Fish_eggs Contains fish egg counts and densities from Neuston tows Date Sampling date cruise Cruise ID (ship-month-year) station Sampling station gear Sampling gear used to collect eggs, in this case a Neuston net mesh Mesh size in microns time_start Time (hhmm) that the tow started time_end Time (hhmm) that the tow ended flow_start Flow meter reading at start of the tow flow_end Flow meter reading at the end of the tow sampleid Unique ID given to the preserved contents of a single net preserve Chemical preservative used comment Comments from the field sampling Eggs Number of fish eggs counted in the subsample Eggs Aliquot Fraction of sample used to count fish eggs (1=entire sample; 0.5=half sample) Remarks comments from the laboratory processing of samples Total fish eggs Total fish eggs in the whole sample (calculated from egg count and aliquot, and then multipled by two because sample was split prior to counting) 7. Neuston_5mm-_Fish Contains larval fish (less than 5mm) counts from Neuston tows Date Sampling date cruise Cruise ID (ship-month-year) station Sampling station time_start Time (hhmm) that the tow started time_end Time (hhmm) that the tow ended flow_start Flow meter reading at start of the tow flow_end Flow meter reading at the end of the tow preserve Chemical preservative used mesh Mesh size in microns sampleid Unique ID given to the preserved contents of a single net dbo_neuston_ring.comment Comments from the field sampling Order_field Order-level fish ID Family Family-level fish ID Taxon Lowest-taxonomic-level fish ID dbo_ichthyoplankton_revised.comment Comments from the laboratory processing of samples Measured Number of larval fish measured Not_Measured Number of larval fish not measured Total Total number of larval fish counted in the subsample Aliquot Fraction of sample used to count and ID larval fish (1=entire sample; 0.5=half sample) Corrected_total Total fish larvae in the whole sample (calculated from fish count and aliquot, and then multipled by two because sample was split prior to counting) 8. Neuston_5mm+_Fish Contains fish (greater than 5mm) counts from Neuston tows Date Sampling date cruise Cruise ID (ship-month-year) station Sampling station time_start Time (hhmm) that the tow started time_end Time (hhmm) that the tow ended flow_start Flow meter reading at start of the tow flow_end Flow meter reading at the end of the tow preserve Chemical preservative used mesh Mesh size in microns sampleid Unique ID given to the preserved contents of a single net dbo_neuston_ring.comment Comments from the field sampling order_field Order-level fish ID family Family-level fish ID Taxon Lowest-taxonomic-level fish ID dbo_ichthyoplankton_5mm_header.comment Comments from the laboratory processing of samples Measured Number of fish measured Not_Measured Number of fish not measured Total Total number of fish counted in the sample (greater than 5mm fish are not subsampled; i.e., all are counted) 9. Neuston_5mm-_Fish_lengths Contains larval fish (less than 5mm) counts and body lengths from Neuston tows date Sampling date cruise Cruise ID (ship-month-year) station Sampling station gear Sampling gear used to collect eggs, in this case a Neuston net mesh Mesh size in microns time_start Time (hhmm) that the tow started time_end Time (hhmm) that the tow ended flow_start Flow meter reading at start of the tow flow_end Flow meter reading at the end of the tow sampleid Unique ID given to the preserved contents of a single net preserve Chemical preservative used dbo_neuston_ring_comment Comments from the field sampling taxon Lowest-taxonomic-level fish ID dbo_ichthyoplankton_revised_comment Comments from the laboratory processing of samples Aliquot Fraction of sample used to count and ID larval fish (1=entire sample; 0.5=half sample) Measured Number of larval fish measured Not_Measured Number of larval fish not measured Total Total number of larval fish counted in the subsample Corrected total Total fish larvae in the whole sample (calculated from fish count and aliquot, and then multipled by two because sample was split prior to counting) L[number] Notochord/standard length in mm of fish [number] 10. Neuston_5mm+_Fish_lengths Contains fish (greater than 5mm) counts and body lengths from Neuston tows Date Sampling date cruise Cruise ID (ship-month-year) station Sampling station time_start Time (hhmm) that the tow started time_end Time (hhmm) that the tow ended flow_start Flow meter reading at start of the tow flow_end Flow meter reading at the end of the tow gear Sampling gear used to collect eggs, in this case a Neuston net mesh Mesh size in microns preserve Chemical preservative used sampleid Unique ID given to the preserved contents of a single net dbo_neuston_ring.comment Comments from the field sampling Taxon Lowest-taxonomic-level fish ID dbo_ichthyoplankton_5mm_header.comment Comments from the laboratory processing of samples Measured Number of fish measured Not_Measured Number of fish not measured Total Total number of fish counted in the sample (greater than 5mm fish are not subsampled) length Notochord/standard length in mm of fish (each fish is listed in a separate row) 11. READ ME - Fish Egg IDs 12. Fish Egg Identifications [Anchoa lyolepis, Bascanichthys scuticarus, Calamus leucosteus, Callechelys muraena, Caranx crysos, Chaetodipterus faber, Cyclopsetta chittendeni/fimbriata, Cynoscion arenarius, Cynoscion nothus, Decapterus punctatus, Echeneis naucrates/neucratoides, Engraulidae sp., Equetus lanceolatus, Equetus lanceolatus/Pareques umbrosus, Etropus crossotus, Euthynnus alletteratus, Haemulon aurolineatum, Harengula jaguana, Hemicaranx amblyrhynchus, Lutjanus campechanus, Lutjanus griseus, Menticirrhus americanus, Opisthonema oglinum, Pareques umbrosus/Equetus lanceolatus, Peprilus alepidotus, Peprilus burti, Diplectrum bivittatum, Prionotus longispinosus, Prionotus rubio, Sardinella aurita, Saurida brasiliensis, Scomberomorus brasiliensis, Scomberomorus cavalla, Scomberomorus maculatus, Selene setapinnis, Syacium papillosum, Symphurus plagiusa, Trachinocephalus myops, Trachinotus falcatus, Trichiurus lepturus, Xyrichtys novacula, Unknown] Sample number, Date, Filtered Volume (m^3), Total number of eggs in Sample, Number of Eggs Barcoded.