Table of Contents

• Coverage
• Dataset Description
  • Methods & Sampling
  • Data Processing Description
• Data Files
• Supplemental Files
• Related Publications
• Related Datasets
• Parameters
• Project Information
• Funding

This dataset includes only the sessile organism abundance data from the study. See "Related Datasets" section for mobile species percent cover data.

Surveys were conducted at John Brown’s Beach (57.05 N, 135.37 W), near Sitka, Alaska, USA. Specific site information is included in the file "Tide_Pool_Characteristics.csv" under Supplemental Files.

Sampling and analytical procedures:
We selected 36 tide pools to study and surveyed each using a flexible quadrat with 10cm x 10cm mesh openings. At the beginning of the survey, the perimeter of each tide pool was delineated using a piece of cord, then the pool was drained using a bilge pump and a bucket. The surveyors then laid down the mesh quadrat and used it to measure the total bottom surface area of the tide pool. The surveyor then identified all non-mobile species (sessile invertebrates and algae) present, measured the surface area occupied by each, and, when finished, refilled the tide pool with the previously removed water. This dataset includes only the sessile organism abundance data from the study. See "Related Datasets" section for mobile species data percent cover data.

Known Issues:
There are multiple small gaps in the data. Dead mussels and dead barnacles were not assessed in the first set of surveys. The time of the pools being drained and refilled was not recorded during the surveys between January and May 2019. There were also a pair of tide pools (22 and 23) that were connected, preventing accurate volume measurements from being taken.

WoRMS Taxa Match:

BCO-DMO checked the provided taxonomic names using the World Register of Marine Species Taxa Match tool (WoRMS). All names matched a known name exactly, though two matched an unaccepted synonym. The following are details on the results of the Taxa Match:

• in dataset: Petrocelis; accepted name: Mastocarpus. The Petrocelis form of Mastocarpus represents a distinct life-history stage. It remains as a separate classification in the data.
• in dataset: Pterosiphonia bipinnata; accepted name: Savoiea bipinnata. This name was changed in the data.

Data Processing:
Data were collected on data sheets and entered into an Excel spreadsheet, where the data were later double-checked against the original data sheets to ensure transfer accuracy.

BCO-DMO Processing 
- Converted dates to YYYY-MM-DD format
- Adjusted field/parameter names to comply with BCO-DMO naming conventions
- Added a conventional header with dataset name, PI names, version date
- Missing data identifier 'empty' replaced with 'nd' (BCO-DMO's default missing data identifier)
- Taxonomic names were checked using the World Register of Marine Species Taxa Match tool (WoRMS). All names matched a known name exactly. Though two matched an unaccepted synonym:
(1) Orgininally labeled Pterosiphonia bipinnata in the dataset, it was changed to the accepted name: Savoiea bipinnata.
(2) Originally labeled Petrocelis matched with Mastocarpus and the submitter requested that Petrocelis remain as a life stage of Mastocarpus.

NSF Award Abstract:
This project addresses fundamental gaps in our knowledge of how changing environmental conditions will impact the earth's species and ecosystems. One of the main challenges is predicting impacts of multiple environmental stressors changing at the same time within highly dynamic ecosystems. Climate simulations in coastal marine habitats will, therefore, yield critical information about likely future changes in biodiversity and ecosystem health. This project is a partnership between institutions with a strong focus on serving underrepresented communities of students, and the investigators are committed to participating in K-12 and undergraduate mentorship programs through their respective institutions. Furthermore, the research will be based in Sitka, Alaska, where investigators will collaborate with the Sitka Sound Science Center to incorporate research into the Scientist in the Schools program and a summer day camp for elementary age children.

This work aims to uncover the trajectory of climate change impacts and interactive responses to multiple climatic stressors on coastal marine species, communities, and ecosystem functioning. To uncover these links, the investigators will (1) quantify seasonal and diel dynamics under ambient conditions in a benthic marine community, (2) conduct factorial manipulations of two climatic stressors - increased carbon dioxide concentrations and temperatures - and measure impacts on physiology, diversity, and productivity, and (3) conduct a second field experiment to evaluate whether productivity responses are due to changes in physiology or biodiversity. Climatic changes have the potential to influence ecosystem functioning by altering physiology, abundance, and community structure (i.e., biodiversity), and this research specifically aims to partition these different pathways, leading to more effective predictions of impacts on benthic marine ecosystems.

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.