Dataset: Squidpop Assays 2021

Name: Results from predation assays (squidpops) conducted along rocky reefs of the Western coast of San Cristobal, Galapagos from June to November 2021 to determine fish predation intensity across a spatial and temporal temperature gradient
Published: 2024-05-17
Keywords: fish, predation, temperature, oceans

Cite This Dataset

DOI:10.26008/1912/bco-dmo.894249.1

Spatial Extent: N:-0.702778 E:-85.584444 S:-0.926667 W:-89.820556

Temporal Extent: 2021-06-29 - 2021-11-15

Project:

The Role of Temperature in Regulating Herbivory and Algal Biomass in Upwelling Systems (Temperature and Herbivory)

Principal Investigator:

John Bruno (University of North Carolina at Chapel Hill, UNC-Chapel Hill)

BCO-DMO Data Manager:

Shannon Rauch (Woods Hole Oceanographic Institution, WHOI BCO-DMO)

Version:

Version Date:

2024-05-17

Restricted:

Validated:

Yes

Current State:

Final no updates expected

Results from predation assays (squidpops) conducted along rocky reefs of the Western coast of San Cristobal, Galapagos from June to November 2021 to determine fish predation intensity across a spatial and temporal temperature gradient

Abstract:

This dataset contains results from predation assays (squidpops) to determine fish predation intensity across a spatial and temporal gradient of temperature. Assays were conducted between June and November 2021 at six locations of rocky reefs along the Western coast of San Cristobal, the eastern Island of the Galapagos Archipelago.

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Archival Copy

Version Date	Archive	Persistent Identifier (PID)	Date PID Issued
2024-05-17	Marine Biological Laboratory/Woods Hole Oceanographic Institution Library (MBLWHOI DLA)	10.26008/1912/bco-dmo.894249.1	2024-05-17

Methods & Sampling

The squidpop assays consiste of the deployment of 25 stakes with small pieces of squid on top for one hour by burying the stakes in sand on the edge of the reefs. After one hour, the number of baits eaten is quantified to estimate predation intensity. Trials were done in six localities during the months of July and November. The study sites were rocky reefs along the Western coast of San Cristobal, the eastern Island of the Galapagos Archipelago.

BCO-DMO Processing

- Imported original files "SquidpopData_2021_updated.xlsx" (data) and "Coordinates_Squidpop2021.xlsx" (site list with coordinates) into the BCO-DMO system.
- Joined the latitude and longitude columns from the site list to the primary data file.
- Renamed fields to comply with BCO-DMO naming conventions.
- Replaced "July2" with "July" in the Month column.
- Converted Date column to YYYY-MM-DD format.
- Created date-time fields in ISO8601 format (both Local and UTC).
- Made latitude and longitude values negative (in the southern and western hemispheres)
- Saved the final file as "894249_v1_squidpop_assays_2021.csv".

Data Files

File
894249_v1_squidpop_assays_2021.csv (Comma Separated Values (.csv), 38.22 KB) MD5:91de68d870a1120d97575f23aeaacc8b Primary data file for dataset ID 894249, version 1

More Information about this dataset

Funding Sources

Funding Source	Award Number
NSF Division of Ocean Sciences	OCE-1737071

Deployments

None available yet

Instruments

Squidpop

Supplied Name:

Supplied Description:

Instrument Type

Generic Name: Squidpop

Generic Description:

The squidpop assay is described in detail in Duffy et al., 2015 (doi: 10.1371/journal.pone.0142994).

In summary, the squidpop consists of a standard prey item: a small piece of dried squid mantle tissue, tethered to a fiberglass plant stake with light monofilament fishing line. The squidpop is assembled by first punching a 1.3-centimeter (cm) diameter disc from the squid mantle using a cork borer. A length of monofilament line is threaded through the squid disc and tied to it securely, then the other end of the line is attached to the end of the plant stake with electrical tape, leaving 1-2 cm of line with the squid piece on the end. The short length of the line helps prevent tangling the tethers when squidpops are bundled together.

Squidpops are deployed by pushing the stakes securely into the substratum. The stakes are typically arranged in one or two rows, but the spatial arrangement is of secondary importance to ensuring that the squidpops can be reliably relocated and retrieved at the end of the deployment. Squidpops are assessed for the presence or absence of the squid bait after some period of time.

Parameters

Date and time formats are described in python strftime() syntax.

Supplied Name	Supplied description	Supplied Units	Standard Name
Year	Year when the assay was conducted Format: %Y	unitless	year
Month	Month when the assay was conducted Format: %B	unitless	month
Date	Date of assay Format: %Y-%m-%d	unitless	date
Time_Local	Time when the squidpop were deployed; local time zone (GMT-6:00) Format: %H:%M	unitless	time_local
ISO_DateTime_Local	Date and time when the squidpop were deployed in ISO 8601 format; local time zone (GMT-6:00) Format: %Y-%m-%dT%H:%M:%S	unitless	ISO_DateTime_Local
ISO_DateTime_UTC	Date and time when the squidpop were deployed in ISO 8601 format; UTC time zone Format: %Y-%m-%dT%H:%MZ	unitless	ISO_DateTime_UTC
Code1	Combination of month and locality	unitless	sample
Locality	Location where assay was conducted	unitless	site
Latitude	Latitude of site where assay was conducted; negative values = South	decimal degrees	lat
Longitude	Longitude of site where assay was conducted; negative values = West	decimal degrees	lon
Season	Whether the assay was conducted during the cold (May-December) or warm season (January-April)	unitless	season
Habitat	Habitat type (reef, rocky reef, or beach)	unitless	site_descrip
Depth	Depth of deployment	meters (m)	depth
Temperature	Water temperature	degrees Celsius	temp
Squidpop	Number of squidpop deployed	unitless	number
Eaten	Whether the bait was eaten (1) or not (0)	unitless	sample_descrip
Code2	Combination of month, locality, and squidpop number	unitless	sample