Seawater temperature in St. John, USVI, 1992-2008 (MCR LTER project, St. John LTREB project)

Website: https://www.bco-dmo.org/dataset/523676
Version: 2014-08-19

Project
» Moorea Coral Reef Long-Term Ecological Research site (MCR LTER)
» LTREB Long-term coral reef community dynamics in St. John, USVI: 1987-2019 (St. John LTREB)

Program
» Long Term Ecological Research network (LTER)
ContributorsAffiliationRole
Edmunds, Peter J.California State University Northridge (CSU-Northridge)Principal Investigator
Brown, Darren JCalifornia State University Northridge (CSU-Northridge)Student
Copley, NancyWoods Hole Oceanographic Institution (WHOI BCO-DMO)BCO-DMO Data Manager


Dataset Description

The objective of this study was to describe how a rare, yet ecologically important invertebrate has changed in abundance over 16 years, and evaluate the extent to which the changes were associated with seawater temperature and storm intensity.

The study was conducted between Cabritte Horn and White Point in the protected Virgin Islands National Park (VINP). The abundance of Millepora spp. on shallow fringing reefs in St. John was quantified from 1992 to 2008 using photoquadrats. Average daily temperature and storm intensity is also reported.

These data were published in Brown D., Edmunds P.J. (2013) Long-term changes in the population dynamics of the Caribbean hydrocoral Millepora spp.  J. Exp. Mar. Biol. Ecol. 441: 62-70. DOI: 10.1016/j.jembe.2013.01.013

Related Datasets:
Millepora colony size 1992-2008
Millepora cover - temps - storms 1992-2008
Millepora cover 1992-2008
storms USVI 1992-2008

Download submitted Excel data file


Acquisition Description

Monitoring began in 1992 using six sites selected at random to characterize the reef community using photoquadrats (0.5×0.5 m). For the present analysis, photoquadrats were pooled among sites to describe the abundance of Millepora spp. on shallow fringing reefs. 

At each site, photoquadrats were scattered randomly along a single transect parallel to the 7-9 m depth contour. Prior to 2000, photoquadrats were recorded using Kodachrome 64 film and a Nikonos V camera fitted with a 28-mm lens and strobes. The camera was mounted on a frame that held it perpendicular to the reef and was used to record ~18 photoquadrats along a 20-m transect. Starting in 2000, digital photography (with strobes and a framer) was introduced, first with a 3.3 megapixel camera (Nikon Coolpix 990), and from 2007, a 6.1 megapixel camera (Nikon D70). Digital photography allowed the sample size to increase to 40 photoquadrats site-1, with the additional photoquadrats scattered along a 20 m extension to the original transect. Both photographic techniques produced images in which objects >=10 mm diameter could be resolved, and the annual surveys (pooled among sites) provided ~102 photoquadrats y-1 prior to 2000, with 210-222 photoquadrats y-1 thereafter. Photoquadrats were recorded between July and August in all years except for 1992, 1993 and 1995-1997 when they were recorded between May and June. Slides were digitally scanned (at 3200 dpi) and together with digital images are archived at mcr.lternet.edu/vinp/data/.

Millepora spp. abundance
The population dynamics of Millepora spp. were quantified using three measures of abundance. Percent cover, colony size (planar area of colonies entirely within the photoquadrat), colonies and branches within each quadrat were counted to evaluate population size (number of colonies). Colonies were counted if they were entirely within the photoquadrat, or if present as encrusting bases located partially within the photoquadrat. These criteria overestimated population sizewhen colonies grewwithmultiple encrusting fronts that separately spread into the photoquadrats.

Temperature and storm intensity
To gain insight into the role of environmental factors in mediating changes in Millepora spp. populations, the associations between abundance and seawater temperature were evaluated using Pearson correlations with census years as replicates. Associations between abundance and storm intensity were evaluated using Spearman correlations as the intensity of storms was evaluated on a categorical scale. 

Seawater temperature in Great Lameshur Bay was recorded using a Ryan Industries thermistor (±0.3 °C accuracy) at 11-m depth from January 1992 to April 1997, and from November 1997 to August 1999; an Optic Stowaway logger (±0.2 °C accuracy) at 9-m depth from May 1997 to October 1997, and from August 1999 to August 2001; and a Hobo Aquapro logger (±0.2 °C accuracy) at 9-m depth from August 2001 to August 2008. Loggers recorded temperature every 15-30 min. Temperature was averaged by day and used to calculate a mean for the ~12 months between samplings. Daily temperatures were used to categorize days as hot (>29.3 °C) or cold (<=26.0 °C), and the number of hot and cold days in each year was used to evaluate the association between thermally extreme days and Millepora spp. abundance. The temperature defining "hot days" was determined by the coral bleaching threshold for St. John (http://www.coral.noaa.gov/research/climate-change/coral-bleaching. html), and the temperature defining "cold days" was taken as 26.0 °C which marks the lower 12th percentile of all daily temperatures between 1989 and 2005 (Edmunds, 2006).

To analyze the impacts of storms on Millepora spp., storms occurring between sampling intervals were ranked by their potential damaging effects, and the ranks summed over each sampling year to assess the annual impact on benthic taxa. The potential impacts of storms were evaluated from their greatest wind speeds on St. John, which were used as a proxy for the size ofwaves resulting from the closest passage to the south of the island. Wind speeds were used to rank storms on a four-step scale: 1 <= 25 km h-1, 25 kmh-1 < 2 <= 50 km h-1, 50 km h-1 < 3 <= 75 km h-1, and 4 > 75 km h-1.

Wind speeds in St. John were estimated using summaries of Atlantic hurricane seasons (http://www.nhc.noaa.gov/pastall.shtml), which provided the maximum wind speed of each storm at its closest proximity to St. John, and an exponential function to predict the extent to which the maximum wind speed decayed by the time it impacted the island. The exponential function had the form Sd=Sm e^(-lambda*d) where Sd is the local wind speed, Sm is the maximum wind speed at the closest distance (d) to the south coast of St. John, and lambda a constant. lambda was determined empirically for six storms (Hortense, Georges, Lenny, Jose, Debby, and Earl) for which wind speed was recorded at the Cyril E. King Airport, St. Thomas, 25-km west of Lameshur Bay; wind speed was best predicted with lambda=0.016 (r2=0.659, n=6). Wind speeds on the south coast of St. John resulting from the close passage of major storms were therefore predicted using Sd=Sme^(-0.016*d).


Processing Description

BCO-DMO Processing Notes:

- original file: Millepora_long_term _metadata copy.xlsx
- added conventional header with dataset name, PI name, version date
- moved columns so that date is first
- added year, month, day in order to display by year month
- reformated date from mm/dd/yyyy to yyyy/mm/dd
- replaced blank cells with 'nd'

 


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Parameters

ParameterDescriptionUnits
yearyear YYYY
month_localmonth; local time MM
day_localday; local time DD
date_locallocal date YYYY/MM/DD
tempaverage daily seawater temperature degrees Celsius


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Instruments

Dataset-specific Instrument Name
camera
Generic Instrument Name
Camera
Dataset-specific Description
1992-1999: Nikonos V film camera using Kodachrome 64 film 2000-2006: Nikon Coolpix 990 - 3.3 megapixel digital camera 2007-2008: Nikon D70 - 6.1 megapixel digital camera  
Generic Instrument Description
All types of photographic equipment including stills, video, film and digital systems.

Dataset-specific Instrument Name
Water Temp Sensor
Generic Instrument Name
Water Temperature Sensor
Dataset-specific Description
1992-1997: Ryan Industries thermistor (±0.3 °C accuracy) 1997: Optic Stowaway logger (±0.2 °C accuracy) 2001-2008: Hobo Aquapro logger (±0.2 °C accuracy  
Generic Instrument Description
General term for an instrument that measures the temperature of the water with which it is in contact (thermometer).


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Deployments

Edmunds_VINP

Website
Platform
Virgin Islands National Park
Start Date
1987-01-01
End Date
2016-09-01
Description
Studies of corals and hermit crabs


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Project Information

Moorea Coral Reef Long-Term Ecological Research site (MCR LTER)


Coverage: Island of Moorea, French Polynesia


From http://www.lternet.edu/sites/mcr/ and http://mcr.lternet.edu/:
The Moorea Coral Reef LTER site encompasses the coral reef complex that surrounds the island of Moorea, French Polynesia (17°30'S, 149°50'W). Moorea is a small, triangular volcanic island 20 km west of Tahiti in the Society Islands of French Polynesia. An offshore barrier reef forms a system of shallow (mean depth ~ 5-7 m), narrow (~0.8-1.5 km wide) lagoons around the 60 km perimeter of Moorea. All major coral reef types (e.g., fringing reef, lagoon patch reefs, back reef, barrier reef and fore reef) are present and accessible by small boat.

The MCR LTER was established in 2004 by the US National Science Foundation (NSF) and is a partnership between the University of California Santa Barbara and California State University, Northridge. MCR researchers include marine scientists from the UC Santa Barbara, CSU Northridge, UC Davis, UC Santa Cruz, UC San Diego, CSU San Marcos, Duke University and the University of Hawaii. Field operations are conducted from the UC Berkeley Richard B. Gump South Pacific Research Station on the island of Moorea, French Polynesia.

MCR LTER Data: The Moorea Coral Reef (MCR) LTER data are managed by and available directly from the MCR project data site URL shown above.  The datasets listed below were collected at or near the MCR LTER sampling locations, and funded by NSF OCE as ancillary projects related to the MCR LTER core research themes.

The following publications and data resulted from this project:

2012 Edmunds PJ. Effect of pCO2 on the growth, respiration, and photophysiology of massive Porites spp. in Moorea, French Polynesia. Marine Biology 159: 2149-2160. doi:10.1594/PANGAEA.820375
Porites growth_respiration_photophys
Download complete data for this publication (Excel file)


LTREB Long-term coral reef community dynamics in St. John, USVI: 1987-2019 (St. John LTREB)


Coverage: St. John, U.S. Virgin Islands; California State University Northridge


Long Term Research in Environmental Biology (LTREB) in US Virgin Islands:

From the NSF award abstract:
In an era of growing human pressures on natural resources, there is a critical need to understand how major ecosystems will respond, the extent to which resource management can lessen the implications of these responses, and the likely state of these ecosystems in the future. Time-series analyses of community structure provide a vital tool in meeting these needs and promise a profound understanding of community change. This study focuses on coral reef ecosystems; an existing time-series analysis of the coral community structure on the reefs of St. John, US Virgin Islands, will be expanded to 27 years of continuous data in annual increments. Expansion of the core time-series data will be used to address five questions: (1) To what extent is the ecology at a small spatial scale (1-2 km) representative of regional scale events (10's of km)? (2) What are the effects of declining coral cover in modifying the genetic population structure of the coral host and its algal symbionts? (3) What are the roles of pre- versus post-settlement events in determining the population dynamics of small corals? (4) What role do physical forcing agents (other than temperature) play in driving the population dynamics of juvenile corals? and (5) How are populations of other, non-coral invertebrates responding to decadal-scale declines in coral cover? Ecological methods identical to those used over the last two decades will be supplemented by molecular genetic tools to understand the extent to which declining coral cover is affecting the genetic diversity of the corals remaining. An information management program will be implemented to create broad access by the scientific community to the entire data set.

The importance of this study lies in the extreme longevity of the data describing coral reefs in a unique ecological context, and the immense potential that these data possess for understanding both the patterns of comprehensive community change (i.e., involving corals, other invertebrates, and genetic diversity), and the processes driving them. Importantly, as this project is closely integrated with resource management within the VI National Park, as well as larger efforts to study coral reefs in the US through the NSF Moorea Coral Reef LTER, it has a strong potential to have scientific and management implications that extend further than the location of the study.

The following publications and data resulted from this project:

2015    Edmunds PJ, Tsounis G, Lasker HR (2015) Differential distribution of octocorals and scleractinians around St. John and St. Thomas, US Virgin Islands. Hydrobiologia. doi: 10.1007/s10750-015-2555-z
octocoral - sp. abundance and distribution
Download complete data for this publication (Excel file)

2015    Lenz EA, Bramanti L, Lasker HR, Edmunds PJ. Long-term variation of octocoral populations in St. John, US Virgin Islands. Coral Reefs DOI 10.1007/s00338-015-1315-x
octocoral survey - densities
octocoral counts - photoquadrats vs. insitu survey
octocoral literature review
Download complete data for this publication (Excel file)

2015   Privitera-Johnson, K., et al., Density-associated recruitment in octocoral communities in St. John, US Virgin Islands, J.Exp. Mar. Biol. Ecol. DOI 10.1016/j.jembe.2015.08.006
octocoral recruitment
Download complete data for this publication (Excel file)

2014    Edmunds PJ. Landscape-scale variation in coral reef community structure in the United States Virgin Islands. Marine Ecology Progress Series 509: 137–152. DOI 10.3354/meps10891.
Data at MCR-VINP.
Download complete data for this publication (Excel file)

2014    Edmunds PJ, Nozawa Y, Villanueva RD.  Refuges modulate coral recruitment in the Caribbean and Pacific.  Journal of Experimental Marine Biology and Ecology 454: 78-84. DOI: 10.1016/j.jembe.2014.02.00
Data at MCR-VINP.
Download complete data for this publication (Excel file)

2014    Edmunds PJ, Gray SC.  The effects of storms, heavy rain, and sedimentation on the shallow coral reefs of St. John, US Virgin Islands.  Hydrobiologia 734(1):143-148.
Data at MCR-VINP.
Download complete data for this publication (Excel file)

2014    Levitan, D, Edmunds PJ, Levitan K. What makes a species common? No evidence of density-dependent recruitment or mortality of the sea urchin Diadema antillarum after the 1983-1984 mass mortality.  Oecologia. DOI 10.1007/s00442-013-2871-9.
Data at MCR-VINP.
Download complete data for this publication (Excel file)

2014    Lenz EA, Brown D, Didden C, Arnold A, Edmunds PJ.  The distribution of hermit crabs and their gastropod shells on shallow reefs in St. John, US Virgin Islands.  Bulletin of Marine Science 90(2):681-692. http://dx.doi.org/10.5343/bms.2013.1049
Data at MCR-VINP.
Download complete data for this publication (Excel file)

2013    Edmunds PJ.  Decadal-scale changes in the community structure of coral reefs in St. John, US Virgin Islands.  Marine Ecology Progress Series 489: 107-123.
Data at MCR-VINP.
Download complete data for this publication (zipped Excel files)

2013    Brown D, Edmunds PJ.  Long-term changes in the population dynamics of the Caribbean hydrocoral Millepora spp.  J. Exp Mar Biol Ecol 441: 62-70. doi: 10.1016/j.jembe.2013.01.013
Millepora colony size
Millepora cover - temps - storms 1992-2008
Millepora cover 1992-2008
seawater temperature USVI 1992-2008
storms USVI 1992-2008
Download complete data for this publication (Excel file)

2012    Brown D, Edmunds PJ. The hermit crab Calcinus tibicen lives commensally on Millepora spp. in St. John, United States Virgin Islands.  Coral Reefs 32: 127-135. doi: 10.1007/s00338-012-0948-2
crab abundance and coral size
crab displacement behavior
crab nocturnal surveys
crab predator avoidance
Download complete data for this publication (Excel file)

2011    Green DH, Edmunds PJ.  Spatio-temporal variability of coral recruitment on shallow reefs in St. John, US Virgin Islands.  Journal of Experimenal Marine Biology and Ecology 397: 220-229.
Data at MCR-VINP.
Download complete data for this publication (Excel file)

2011    Colvard NB, Edmunds PJ. (2011) Decadal-scale changes in invertebrate abundances on a Caribbean coral reef.  Journal of Experimental Marine Biology and Ecology. 397(2): 153-160. doi: 10.1016/j.jembe.2010.11.015
benthic invert codes
inverts - Tektite and Yawzi Pt
inverts - pooled
Download complete data for this publication (Excel file)



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Program Information

Long Term Ecological Research network (LTER)


Coverage: United States


adapted from http://www.lternet.edu/

The National Science Foundation established the LTER program in 1980 to support research on long-term ecological phenomena in the United States. The Long Term Ecological Research (LTER) Network is a collaborative effort involving more than 1800 scientists and students investigating ecological processes over long temporal and broad spatial scales. The LTER Network promotes synthesis and comparative research across sites and ecosystems and among other related national and international research programs. The LTER research sites represent diverse ecosystems with emphasis on different research themes, and cross-site communication, network publications, and research-planning activities are coordinated through the LTER Network Office.

LTER site location map

2017 LTER research site map obtained from https://lternet.edu/site/lter-network/



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Funding

Funding SourceAward
NSF Division of Environmental Biology (NSF DEB)
NSF Division of Environmental Biology (NSF DEB)

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