logo
 
 
 
 
PBCRRT Home  
 
 
 

Information
 
 
 
 

Dive Reports
 
 
 

Fish Reports
 
 
 

Team Photos
 
 

 
 

Operations Manual
 
 
 
 
Bylaws  
 
 
 
Diving Ops  
 
 
 
Fish Surveying  
 
 
 
Invert Monitoring  
 
 
 
Mapping  
 
 
 
Meetings  
 
 
 
Officer Duties  
 
 
 
Photography  
 
 
 
Report Writing  
 
 
 
Safety  
 
 
 
Training  
 
 
 
Videography  
 
 
 

Training
 
 
 
 

Fish Quizzes
 
 
 
 

The Website Plan
 
 

 
 
 
 
 
Send Email:  
 
 
 
Team Coordinator  
 
 
 
Webmaster  
 


Invertebrate Census Procedures

Another significant effort of the Palm Beach County Reef Research Team is to conduct invertebrate census dives on both artificial and natural reefs of the county. Invertebrate censusing is to be conducted on every site funded by the FWCC grant, using one of the methods described below.

Current Team invertebrate censusing takes two forms: monitoring and surveying.

Monitoring is conducted on reefs that are subject to repeat visits by the Team during a year. The purpose of monitoring is to record change in the invertebrate cover over time, using monitoring stations that have been established at each artificial reef that we revisit.

Surveys are conducted on reefs that will be visited only once per year. The purpose of surveying is to provide a thorough assessment of the invertebrate population as well as relative abundance.

Several techniques are used for both monitoring and surveying, involving photographic, videographic, and in situ evaluation by the divers, depending on the requirement for the site. The Photographic Point-Sampling Method is used on each monitored site, and will be continued. The Videographic Invertebrate Survey Method is the method of choice for sites that are surveyed annually. For the FY2003-2004 grant, the Roving Invertebrate Survey Method will be added, and will be used on selected new sites to evaluate its merit. In the case of the photographic and videographic techinques, the data collected is further reduced after the dives before inclusion in the database.

For new sites on the FY2003/2004 Grant, censusing locations/areas will be selected as appropriate for the method to be utilized, and added to the maps as they are developed.

The following section provides the procedural approach to be used for the various tasks of the Invetebrate Monitoring Specialty, for each survey method.

Photographic Point-Sampling Method:

  • Data Collection:

    Monitoring stations for bottom cover have been established at each artificial reef, and are shown on the Team maps. Where practical, benchmarks have been placed at these monitoring stations. Where the placement of benchmarks is not practical (the hull or superstructure of a ship, for example) the photos are taken relative to an easily identifiable landmark (such as a port hole). Photos are Photos are taken at a distance of half a meter, perpendicular to the substrate, at the 3, 6, 9, and 12 o’clock positions relative to these benchmarks. Multiple photographs are taken at a distance of 2 ft. perpendicular to the substrat, and must be taken at the same locations each time the site is monitored in order to accurately assess changes in invertebrate cover over time.

  • Slide analysis: Slide are projected onto a 10x10 grid. The data sheet contains a list of 25 randomly generated numbers, which are used to select the cells to be analyzed. The organism covering the majority of the area within this cell is identified to the lowest taxonomic level possible and recorded on the data sheet. Twelve to fifteen slides from each site, covering all the ID stations, are selected for analysis. The data is then entered into the online database within two weeks following the dive.

Videographic Invertebrate Survey Method:

  • Data Collection:

    A diver conducting a video survey covers as much of the reef as possible, filming the invertebrate cover from a distance of approximately 0.5 meter. The camera is moved slowly so that species can be seen clearly enough to be identified. Any unknown or unusual species encountered should be filmed as carefully as possible in order to capture as much detail as possible to aid positive identification.

  • Video Analysis:

    Following the dive, this video, (which will generally be the same as the documentary video routinely filmed on Team dives), is transferred to VHS so that it can be played on a VCR. The data sheet used is the same as that used for the in-water roving invertebrate survey. The tape is viewed and all species seen are identified to the lowest taxonomic level possible and assigned to one of four categories of abundance.

    The categories used are:

    1. : a single individual, or less than 1% cover
    2. : 2-10 individuals, or 1-20% cover
    3. : 11-100 individuals, or 20-50% cover
    4. : >100 individuals, or >50% cover

Roving Diver Invertebrate Survey Method:

  • Data Collection:

    The purpose of the Roving Diver Invertebrate Survey is to provide an inwater assessment of the invertebrate population as well as relative abundance. Data is recorded on an underwater datasheet as the reef is observed. A diver conducting an in-water survey swims over his assigned area, covering it as thoroughly as possible. All species seen are identified to the lowest taxonomic level possible and assigned to one of four categories of abundance.

    The categories used are:

    1. : a single individual, or less than 1% cover
    2. : 2-10 individuals, or 1-20% cover
    3. : 11-100 individuals, or 20-50% cover
    4. : >100 individuals, or >50% cover

    Invertebrates that grow as discrete organisms or well-defined colonies, such as hard coral colonies, gorgonians, vase/barrel/rope sponges, simple tunicates, etc., are assessed as individuals. Organisms that encrust the substrate, or grow in patches, such as encrusting sponges, encrusting bryozoans, algae, etc., are assessed by percent cover.

  • Data Entry:

    The data are then entered into the online database (within two weeks of the dive) and the data sheet is turned over to the Science Coordinator for archival.


PBCRRT Invertebrate Transect Monitoring:

The Team has previously conducted monitored natural reefs using two transect methods: the Substrate Line Transect and the Invertebrate Belt Transect.

Substrate Line Transect:

  • Tape Placement:

    A minimum of two fifty-meter tapes are laid our along the long axis of the reef. The compass heading and depth of the transect are recorded on the data sheet. On subsequent dives to the site, the same starting point and heading will be used. The lead diver swims in a straight line, allowing the tape to feed easily off the reel. The second diver follows, ensuring that the tape is straight and even.

  • Visibility:

    Once the transect tape has been set, the lead diver holds up the data sheet. The second diver swims slowly along the tape until the data sheet can no longer be seen. The distance from the end of the tape to this point is recorded on the data sheet as a measurement of horizontal visibility throught the water.

  • Data Collection:

    Data is collected at each 0.5 meter point along the tape by recording the organism or substrate type present at that point. This will give 100 data points per transect. If the tape is over a rift in the reef the diver swims down to determine what is there. The substrate organism is important, e.g., a Christmas tree worm is in a hard coral; record the hard coral as the data point. There are 2 data sheets per transects. The transect can be started at 0.5 m or at 50 m.

    During the survey:

    • Identify hard corals by shape (branching, mound, star, brain, finger, leaf, other) and by name, if possible. The condition of the coral is noted. Note percent of coral head bleached/dead. Note diseases present on the corals, such as black-band, white-band, yellow-band diseases.

    • Identify gorgonians encountered along the transect, (sea fans are recorded separately).

    • Substrate: Rock/Rubble/Dead Coral/Sand --- Note in “Abiotic” unless dead coral In “Other/Notes” record sponges (kind?), tunicates, mollusks, hydroids, etc. Again, record as much as possible. For algae: “turf” is defined as moss-like; lichen-like; “macro” is anything that has some size or substance to it, e.g. leaves present. If the data point is on a branch of a soft coral on a hard coral, you can check both.

    • Fleshy seaweed: a category by ReefCheck means brown, reds, greens; not calcareous algae, such as Halimeda.

Invertebrate Belt Transect:

  • Tape Placement:

    Two 50 meter tapes are laid end-to-end for a transect length of 100 meters in the same manner as described for the Substrate Lined Transect.

  • Data Collection:

    The transect is divided into four 20 meter lengths, each separated by a 5 meter gap. A 5 meter wide belt, centered on the transect tape, is surveyed from 0 – 20 meters, 25 – 45 meters, 50 – 70 meters, and 75 – 95 meters. The transect area is searched for the following invertebrate species:

    • Pencil Urchin
    • Flamingo Tongue
    • Gorgonian
    • Sea Egg
    • Triton Shell

Invertebrate Monitoring Qualifications:

Both the photographic point source and the videographic transect methods allow the data to be collected by non Invertebrate specialists. The data is then reduced after the dive, where reference books can be utilized to get an exact species identification. Thus Team members can do the task without being Invertebrate Monitoring specialists. This provides an excellent training mechanism for learning the invertebrates.

The Roving Diver Invertebrate Survey requires the Team member to know the common invertebrate taxonomy to the species level and be able to identify the species on sight, to record it on the form as it is observed during the dive. This will eventually become the preferrecd method of the team, requiring the member be qualified as an Invertebrate Monitoring specialist.

To become certified as a PBCRRT Invert Monitoring Specialist, a member must:

  • Complete the Research Diver Orientation Class.
  • Score 90% or better on an invertebrate identification test involving 50 invertebrates randomly picked from the Master Invert List
  • participate in a in at least 6 in-water invertebrate monitoring dives (3 dive trips) on regular Team dives, under the tutelage of a qualified Invert Monitoring specialist. After each dive, the qualified specialist will determine the accuracy of the underwater monitoring done by the trainee. Upon satisfactory completion of this step, the trainee will become a qualified Invertebrate Monitoring Specialist.
  • Invertebrate Monitoring Specialists must recertify by passing the Invert ID test annually.