| Contributors | Affiliation | Role |
|---|---|---|
| Pierson, James J. | University of Maryland Center for Environmental Science (UMCES/HPL) | Principal Investigator |
| Decker, Mary Beth | Yale University | Co-Principal Investigator |
| Allison, Dicky | Woods Hole Oceanographic Institution (WHOI BCO-DMO) | BCO-DMO Data Manager |
Cruise metadata from the Gelatinous Zooplankton portion of the Dead Zone Zooplankton project. Includes gear types and mesh sizes, locations, dissolved oxygen in the water column,depths sampled and volume of water filtered.
| File |
|---|
cruise_data.csv (Comma Separated Values (.csv), 106.79 KB) MD5:15f23171e67a35817f1a06a25bb604b3 Primary data file for dataset ID 521596 |
| Parameter | Description | Units |
| cruise | Internal cruise identifier: Dead Zone Zooplankton: First two digits denote Year (10=2010; 11=2011) Last two digits denote cruise number for that year | text |
| cruise_official | UNOLS cruise identifier | text |
| station | Station Count | number |
| lat | Latitude | degrees |
| lon | Longitude | degrees |
| sample_ID | Unique ID for each Sample (#-AAA-#-#) First number is station; Letters denote gear type; second number is gear deployment sequence [called cast by DMO]; third number is Net number per deployment; broken up into its component parts to be served | alphanumeric |
| cast | gear deployment sequence | number |
| net | net number per deployment | number |
| occupation | relative geolocation: South station near mouth of Rappohannock River; North station near mouth of Choptank River | text |
| year | Year | 4-digit year |
| month_local | month | number |
| day_local | day of the month | number |
| time_local | time of net tow | HH:MM;24-hour clock |
| gear | type of trawl | text |
| mesh | Size of Mesh | microns |
| depth_relative | Depth of a net: surface= surface to above pycnocline; pycnocline = through pycnocline; below pycnocline = between bottom and pycnocline; bottom = bottom to below pycnocline | text |
| depth_start_nom | Sampling depth at start of tow | meters |
| depth_end_nom | Sampling depthat end of tow | meters |
| preservation | Type of preservative used for the samples | text |
| tow_duration | Time a net actively fished | minutes |
| vol_filt | Amount of water filtered | cubic meters |
| O2_mg_L_mean | Dissolved Oxygen averaged over the depth of a fishing net | milligrams per liter |
| time_accuracy | Percent of time net fished within designated depths to an accuracy of plus or minus 1 minute | minutes |
| ISO_DateTime_Local | ISO standard formatted Time | alphanumeric |
| comments | notes | text |
| Dataset-specific Instrument Name | MOCNESS |
| Generic Instrument Name | MOCNESS |
| Generic Instrument Description | The Multiple Opening/Closing Net and Environmental Sensing System or MOCNESS is a family of net systems based on the Tucker Trawl principle. There are currently 8 different sizes of MOCNESS in existence which are designed for capture of different size ranges of zooplankton and micro-nekton Each system is designated according to the size of the net mouth opening and in two cases, the number of nets it carries. The original MOCNESS (Wiebe et al, 1976) was a redesigned and improved version of a system described by Frost and McCrone (1974).(from MOCNESS manual) This designation is used when the specific type of MOCNESS (number and size of nets) was not specified by the contributing investigator. |
| Dataset-specific Instrument Name | Tucker Trawl |
| Generic Instrument Name | Tucker Trawl |
| Dataset-specific Description | Gelatinous zooplankton samples were collected with a 280 micron-meshed Tucker Trawl. |
| Generic Instrument Description | The original Tucker Trawl, a net with a rectangular mouth opening first built in 1951 by G.H. Tucker, was not an opening/closing system, but shortly thereafter it was modified so that it could be opened and closed. The original had a 183 cm by 183 cm flexible rectangular mouth opening 914 cm long net with 1.8 cm stretched mesh for the first 457 cm and 1.3 cm mesh for last 457 cm. 152 cm of coarse plankton or muslin netting lined the end of the net. Tucker designed the net to collect animals associated with the deep scattering layers, principally euphausiids, siphonophores, and midwater fish. (from Wiebe and Benfield, 2003). Currently used Tucker Trawls usually have 1-m2 openings and can have a single net or multiple nets on the frame. |
| Website | |
| Platform | R/V Hugh R. Sharp |
| Report | |
| Start Date | 2010-05-24 |
| End Date | 2010-06-01 |
| Description | Cruise in Main Channel of Chesapeake Bay |
| Website | |
| Platform | R/V Hugh R. Sharp |
| Start Date | 2010-08-19 |
| End Date | 2010-08-26 |
| Description | Cruise in main channel of Chesapeake Bay to collect zooplankton samples. |
| Website | |
| Platform | R/V Hugh R. Sharp |
| Start Date | 2010-09-21 |
| End Date | 2010-09-27 |
| Description | One of a series of cruises in the main channel of the Chesapeake Bay to collect gelatinous zooplankton. |
| Website | |
| Platform | R/V Hugh R. Sharp |
| Start Date | 2011-05-24 |
| End Date | 2011-06-01 |
| Description | One of six week-long cruises in the main channel of Chesapeake Bay to collect gelatinous zooplankton. |
| Website | |
| Platform | R/V Hugh R. Sharp |
| Start Date | 2011-07-19 |
| End Date | 2011-07-26 |
| Description | One of six week-long cruises in the main channel of the Chesapeake Bay to collect gelatinous zooplankton |
| Website | |
| Platform | R/V Hugh R. Sharp |
| Start Date | 2011-09-21 |
| End Date | 2011-09-26 |
| Description | One of 6 week-long cruises in the main channel of the Chesapeake Bay, collecting gelatinous zooplankton. |
Description from NSF award abstract:
The occurrence of low-oxygen waters, often called "dead zones" in coastal ecosystems throughout the world is increasing. Despite these increases, the pelagic food-web consequences of low-oxygen waters remain poorly understood. Laboratory research has demonstrated that hypoxic water (< 2 mg l-1) can result in mortality, reduced fitness and lower egg production of planktonic copepods, a major link in food webs supporting pelagic fish. Observations in the sea indicate that hypoxic bottom waters usually have depressed abundances of copepods compared to normoxic waters (> 2 mg l-1). The gradient of declining oxygen concentration with respect to depth (oxycline) can be a critical interface in coastal pelagic ecosystems by altering the migratory behavior and depth distribution of copepods and their spatial coherence with potential predators and prey. This project will result in a mechanistic understanding of how behavior and fitness of copepods are affected by hypoxia. The PIs will compare bottom-up and top-down controls on the ecology of copepods in Chesapeake Bay waters experiencing seasonal hypoxia and those that are normoxic.
Specific objectives of this project are to:
1) analyze changes in migratory behavior and fine-scale (meter) distribution of copepods across the oxycline over hourly and diel time scales while simultaneously examining the distribution and abundance of their food (phytoplankton and microzooplankton) and predators (fish, gelatinous zooplankton);
2) estimate effects of hypoxia on the "fitness" of copepods using a suite of measurements (length/weight ratios, feeding, egg production, and egg hatching success) to develop condition indices of copepods captured at different times and depths in hypoxic and normoxic waters; and
3) evaluate effects of hypoxia on copepod mortality by hypoxia-induced, stage-specific copepod mortality in hypoxic bottom waters and by changes in top-down control of copepods from predation by fish and gelatinous zooplankton.
Oxyclines may be a barrier to vertical migration of copepods and thus disruptive to predator avoidance behavior. Faced with increased predation risk from fish and jellyfish, copepods may seek refuge in hypoxic waters for part of the day and/or make short-term vertical excursions between hypoxic and normoxic waters. By regulating vertical migrations, copepods may increase utilization of microzooplankton prey concentrated in the oxycline. Hypoxic waters may elevate consumption of copepods by jellyfish and depress consumption by pelagic fish. This project will evaluate copepod distribution and migration behavior, individual fitness and stage-specific mortality in hypoxic and normoxic waters. It will examine food-web consequences of increased or decreased spatial coherence of copepods and their predators and prey in regions with hypoxic bottom waters and will contribute to fundamental understanding of food-web processes in eutrophic coastal ecosystems.
Project acronym "DeZoZoo" = "Dead Zone Zooplankton"
| Funding Source | Award |
|---|---|
| NSF Division of Ocean Sciences (NSF OCE) |