United States Virgin Islands Bleaching Response Sampling Protocols

Transcription

1 United States Virgin Islands Bleaching Response Sampling Protocols

2 USVI Bleaching Response Sampling Protocols... 1 USVI Bleaching Response Sampling Protocols... 3 Outline... 3 Tier I... 3 Tier II... Error! Bookmark not defined. Advisory Board... 4 Methods... 4 Tier I... 4 Tier II... 5 Literature Cited and Other Pertinent Sources... 8 Appendix I... 9 Example Sampling Codes... 9 Disease Codes... 9 Coral Health Categories... 9 Species Codes... 10

3 USVI Bleaching Response Sampling Protocols Outline Tier I Tier II Concerned public with little background in marine science Brief online or workshop training Reconnaissance of targeted reef habitats, geographic regions and physical regimes GPS or map estimation of surveyed area On spot assessment of presence or absence of bleaching Roving swim or wading: o Estimates of intensity 1 (extent of colony affected) lightest and darkest colony color values from Coral Watch Cards (if available) and intensity categories (percent of colony in lightest category) from Reef Managers Guide to Coral Bleaching o Estimates of severity 2 (prevalence), photographic Marine professionals with recurring experience in coral reef environments; expertise or experience in ecological assessments or coral reef ecosystems Workshop training Reconnaissance of target reef habitats, geographic regions and physical regimes On spot assessment of presence or absence of bleaching/disease Directional swim: o Estimates of bleaching/disease intensity by species lightest and darkest colony color values from Coral Watch Cards (if available) and intensity categories (percent of colony in lightest category) from Reef Managers Guide to Coral Bleaching o Estimates of bleaching/ disease severity, photographic and video o Estimates of mortality Purpose: For differing habitats, estimation of bleaching intensity and severity, estimation of levels of whole colony and coral cover mortality, estimation of the mechanisms of colony mortality, such as diseases, interactions with predators (e.g., damselfish, competitors (e.g., macroalgae, cyanobacteria, and epibenthic sponges), and parasites (e.g., Clionid sponges) Workshop training 1 Intensity. Equal to the degree of affect on individual colonies as either lightest and darkest color values and percent of colonies affected by lightest color value or percent of colony affected by disease lesion. 2 Severity. Equal to the number of individuals affected in a given population (prevalence). Population in this case is the sampled colonies in a given area.

4 Reconnaissance of target reef habitats, geographic regions and physical regimes On spot assessment of presence or absence of bleaching/disease Transects using modified AGRAA: o Estimates of severity by species o Estimates of prevalence, photographic and video o Estimates of mortality Advisory Board Creation of prioritization of target reef habitats, geographic regions and physical regimes map and stratified-random sampling points Creation of targeted time periods of assessment Creation of data hand outs and underwater data sheets Creation of online information and data upload portal Coordination of tiered sampling groups Data entry and QA/QC Database management (NOAA, TNC, UVI) Methods Tier I Purpose: The Tier I Reef Assessment Sampling Protocol was developed for the recreational snorkeler/diver that is interested in submitting information on reef health into the Virgin Island Reef Resilience Program dataset. These short surveys are designed to provide a snapshot of local reefs to scientists and managers and may be used to guide where further surveys are conducted in an effort to determine the extent of bleaching and/or the resilience of those reefs. Materials Needed: Diving or snorkeling equipment Underwater clipboard or slate and underwater datasheet, pencils Coral Watch Bleaching cards Submersible digital camera or video camera In field protocol: Complete the observer and site information portions of the VIRRP Tier 1 Reef Assessment Data Sheet. Conduct a 15-minute roving snorkel or dive (or portion of your dive). Pause on each three minute interval and imagine a 1 m 2 (3x3 foot) quadrat (square) overlaid on the reef. Hint: Identifying fixed benthic habitat features for the four points of your quadrat will increase accuracy of data collection. Estimate percent coral coverage

5 and percent bleaching of that quadrat. Record your findings on the VIRRP Tier 1 Reef Assessment Data Sheet. Record any other findings (ex.: number and types of herbivorous fishes, number and types of invertebrates, number and types of diseases, etc.). Take photographs at each of your five survey station and of any important observations or organisms. Note: It is also important to record if no bleaching is observed. Mail or submit your data sheet in person to: Kemit-Amon Lewis, Coral Conservation Manager The Nature Conservancy 3052 Estate Little Princess Christiansted, US Virgin Islands (340) (voice) Or scan and to vicoralreefs@yahoo.com Tier II Purpose: Tier II sampling is designed for those with considerable experience in marine monitoring and is considered a supplement to monitoring activities that may be activated under territorial and federal monitoring programs. The aims are to provide greater spatial and temporal characterization of coral bleaching, disease, and mortality. The more intensive methods to be employed by experienced observers will generate a deeper level of information content on the co-factors that ultimately impinge on coral reproduction, growth, and survival. This level of information can provide greater insight on physical regimes and habitats that provide resistance and resilience to bleaching events, with implications for management of coral reef systems under the threat of increasing frequency and severity of extreme high seawater temperature events. Sampling will involve threelevels of protocol sampling: (1) Bleaching/Disease Severity and Intensity Surveys (hereafter Bleaching Surveys), (2) Mortality Estimation Surveys (hereafter Mortality Surveys), and (3) Individual Marked Colony Surveys. Mortality Surveys will involve the same methodologies as the Bleaching Surveys with the addition of temporary marking of the transect survey path for re-visitation at time points after the initial sampling. Bleaching/Disease Severity and Intensity Surveys Materials Needed: Magnetic underwater compass 10 m transect line Diving equipment Underwater clipboard or slate and underwater paper, pencils Coral Watch Bleaching cards Flagging tape and/or small foam buoys Submersible digital camera or video camera

6 In field Protocol: Diver pairs will survey random sampling points generated by the coordinators following established protocols (Kramer et al. 2005; Smith et al. 2010). Sampling points will be located with GPS and marked at the water surface with a drop buoy. Diver pairs will descend on the drop buoy to the sampling point a at the location of the buoy drop weight. Sampling will commence if the area is determined to be suitable; i.e., the presence of hard corals along proposed compass direction. If area is unsuitable then check area along next random compass heading. If the entire potential sampling area is unsuitable, then end dive. If the sampling area is suitable divers will deploy a 10 m transect line along a predetermined random compass heading. For Mortality Surveys beginning and terminus of the transect will be marked (see following schedule). Diver 1 will deploy the transect along predetermined compass point while Diver 2 will begin health assessment of corals along transect. Diver 1 will return along laid transect filming the right side of the transect with a digital still or video camera. When completed divers will retrieve the transect and ascend. Coral Health Sampling. Normally, selection of coral colonies will be by linear intercept of all hard coral colonies under the transect line, including Milleporids (fire corals). For areas with sparse corals, the diver may elect to use a 10 cm wide belt transect along the left side of the transect line and assess health of all corals intercepted by the belt. The object is to sample as many colonies as possible within linear distance described by the 10 m transect 3. Coral health sampling will follow modified AGRAA sampling protocols (Smith et al. 2008; Appendix I). Each colony is assessed in situ for species identity, size, disease presence and intensity, bleaching presence and intensity (color and extent), old and recent partial mortality, and interactions with predators, competitors, and parasites (See Appendix 1 for expanded description of categories). Data should be entered into data entry sheets and given to data processing coordinator. Benthic Cover Sampling. Benthic cover is sampled using still or video along the transect line (Carleton and Done 1985; Rogers et al. 2001). The site name and date should be recorded as a picture or video clip immediately before the filming of the transect. For transect filming, the camera should be held perpendicular to the substrate at approximately 0.4 to 1.0 meter off the surface. A dropper weight on a string is useful to get the correct spacing. The full 10 m of the transect should be filmed, or the maximum length allowed to maintain safe dive times. Following data retrieval the pictures files should be labeled by site name, date, and sequence number. Non-overlapping video images should be captured and labeled similarly or full video cassettes or clips should be sent to the data processing 3 Detection of rare disease will be aided by larger sample sizes. For example, in epidemiology for a disease with 1% prevalence in a community there is a 63% chance of detection if 100 individuals are sampled, and a 95% chance of detection if 300 individuals are sampled.

7 coordinator. Still images will be processed with Coral Point Count (Kohler and Gill 2006, to determine benthic cover. Mortality Estimation Surveys Methods as in Bleaching Surveys, however, beginning and terminus of transect are marked with biodegradable flagging tape. Sites are to be revisited in recovery phase of bleaching (typically January May) and one year following bleaching to assess prevalence of post-bleaching disease and extent of coral cover mortality. Individual Marked Colony Surveys Materials Needed: Magnetic underwater compass 10 m transect line Diving equipment Underwater clipboard or slate and underwater paper, pencils Coral Watch Bleaching cards Aluminum tags or similar Submersible digital camera or video camera Information on individual marked colonies provides a higher degree of information on threats to reproduction, growth, and survival and can give species-specific mortality rates. This is critical to predicting the population trajectories of coral reefs and shifts in species composition. Individual colony assessments provide an understanding of the differing levels of partial mortality versus whole colony mortality and, thus, the ability of corals to reestablish coral cover through regrowth (potentially faster) or resettlement of new coral larvae (potentially slower).

8 Literature Cited and Other Pertinent Sources Carleton JH, Done TJ (1995) Quantitative video sampling of coral reef benthos: Large-scale application. Coral Reefs 14:35-46 Kohler K, Gill SM (2006) Coral Point Count with Excel extensions (CPCe): A Visual Basic program for the determination of coral and substrate coverage using random point count methodology. Computers and Geosciences 32: Kramer P, Lang J, Marks K, Garza-Perez R, Ginsburg R (2005) AGRRA Methodology, version 4.0, June University of Miami, Miami Miller J, Muller E, Rogers C, Waara R, Atkinson A, Whelan K, Patterson M, Witcher B (2010) Coral disease following massive bleaching in 2005 causes 60% decline in coral cover on reefs in the US Virgin Islands. Coral Reefs 28: Rogers CS, Garrison G, Grober R, Hillis Z, Franke M (2001) Coral Reef Monitoring Manual for the Caribbean and Western Atlantic. US National Park Service, St. John Smith TB, Nemeth RS, Blondeau J, Calnan JM, Kadison E, Herzlieb S (2008) Assessing coral reef health across onshore to offshore stress gradients in the US Virgin Islands. Marine Pollution Bulletin 56: Smith TB, Blondeau J, Nemeth RS, Pittman SJ, Calnan JM, Kadison E, Gass J (2010) Benthic structure and cryptic mortality in a Caribbean mesophotic coral reef bank system, the Hind Bank Marine Conservation District, U.S. Virgin Islands. Coral Reefs 29:

9 Appendix I Example Sampling Codes Disease Codes Dark Spots Disease (DSD) Black Band Disease (BBD) White Plague Disease (PLA) Yellow Blotch/Band Disease (YBD) Unknown Disease or Recent Lesions, Dead Coral (DCOR) Intercostal Mortality Syndrome (DCOR A) Coral Health Categories Size. Maximum width is the maximum planar diameter, Minimum Width is perpendicular to max. planar width % Disease/Bleaching/Impairment/Interaction. Area estimate are the three dimensional proportion of the colony's living tissue affected. Bleaching. "SP" = slightly pale, "P" = Pale, "VP" = very pale, "BL" = Bleached, "PB" = some level of paling (used in earlier assessments) CW I/II. The lightest and darkest colors of colony living tissue corresponding to the Coral Watch scale ( Recent partial mortality, skeleton not eroded (fine corallite structure still intact) and bare or with a thin veneer of sheeting or filamentous algae, is typically visible for up to three months following tissue loss. Old partial mortality, skeleton eroded and covered with turf or macroalgae, is a transition from recent mortality and typically lasts up to 1 4 years (see and Smith TB, Nemeth RS, Blondeau J, Calnan JM, Kadison E, Herzlieb S (2008) Assessing coral reef health across onshore to offshore stress gradients in the US Virgin Islands. Marine Pollution Bulletin 56: ). Impairment. Colony shows at least one sign of disease, mortality, predation, or interaction Corallivore. Type and number of corallivores Predation. Type and number of predators

10 Interaction. Percent living tissue interacting with potential competitors. SPO = Non-boring Sponge, CYANO/LYNG/SCX = cyanobacteria/lyngbia/schizothrix, DICT = Dictyota, HALI- = Halimeda, LOBO = Lobophora, SARG = Sargassum, SED = Sediment. % Interaction. For non-boring sponges, macroalgae (not cyanobacteria), and sediment, percentages are proportion of living tissue covered. For cyanobacteria of any species, percentages are linear proportion of border contact. For Cliona, percentages are percent of living and dead colony area bored by sponge. Species Codes Acropora cervicornis (AC) - coral Acropora palmata (AP) - coral Acropora prolifera (APR) - coral Agaricia agaricites (AA) - coral Agaricia fragilis (AF) - coral Agaricia grahamae (AG) - coral Agaricia humilis (AH) - coral Agaricia lamarcki (AL) - coral Agaricia tenuifolia (AT) - coral Agaricia undata (AU) - coral Agaricia species (AGSP) - coral Colpophyllia natans (CN) - coral Dendrogyra cylindrus (DCY) - coral Diploria clivosa (DC) - coral Diploria labyrinthiformis (DL) - coral Diploria strigosa (DS) - coral Dichocoenia stokesii (DSO) - coral Eusmilia fastigiata (EF) - coral Favia fragum (FF) - coral Isophyllia sinuosa (IS) - coral Isopyhyllastrea rigida (IR) - coral Leptoseris cucullata (LC) - coral Manicina areolata (MAR) - coral Madracis decactis (MD) - coral Madracis formosa (MAFO) - coral Madracis mirabilis (MM) - coral Meandrina meandrites (MME) - coral Montastraea annularis (MA) - coral Montastraea annularis complex (MACX) - coral Montastraea cavernosa (MC) - coral Montastraea faveolata (MFAV) - coral Montastraea franksi (MFRA) - coral Montastraea species (MSPP) - coral

11 Mussa angulosa (MAN) - coral Mycetophyllia aliciae (MAL) - coral Mycetophyllia danaana (MDA) - coral Mycetophyllia lamarckiana (ML) - coral Mycetophyllia ferox (MF) - coral Mycetophyllia species (MYSP) - coral Oculina diffusa (OD) - coral Porites astreoides (PA) - coral Porites branneri (PB) - coral Porites divaricata (PD) - coral Porites furcata (PF) - coral Porites porites (PP) - coral Porites branching species (PBSP) - coral Scolymia cubensis (SC) - coral Scolymia lacera (SL) - coral Scolymia species (SCSP) - coral Siderastrea radians (SR) - coral Siderastrea siderea (SS) - coral Siderastrea species (SSPP) - coral Solenastrea bournoni (SB) - coral Solenastrea hyades (SH) - coral Stephanocoenia intercepta (SI) - coral Tubastraea coccinea (TC) - coral Millepora alcicornis (MILA) - coral Millepora complanata (MILC) - coral Millepora squarrosa (MILS) - coral