Post monitoring

data collection


Monitoring is the repeated observation of a system, usually to detect change.  Environment monitoring programs provide coastal management agencies with data to make evidenced-based decisions and policy.


Seagrass-Watch long-term monitoring started early August 1999. More than 26 countries participate in the program globally and seagrass monitoring is currently occurring at more than 335 sentinel sites and growing.

Each Seagrass monitoring event usually takes about two hours to complete, once you have become familiar with the methods.

How frequent your monitor your seagrass site, is at the discretion and capacity of participants.

When starting your seagrass monitoring, we recommend four monitoring events in the first year (every 3 months) to provide an understanding of seagrass seasonality.

For long-term seagrass monitoring, we recommend monitoring at least once a year, around the same time each year.


Seagrass-Watch has several seagrass monitoring strategies depending on the type and location of seagrass meadows. Below we describe the most popular method (Permanent Transects).

IF you do not think the method is suitable for your seagrass meadows (for example, the seagrass meadow is subtidal or not of a size able to contain a 50m by 50m site), alternative strategies are available in the Seagrass-Watch manual or contact Seagrass-Watch HQ for advice.


All seagrass monitoring dates and times are provided by local coordinators and monitoring groups. Seagrass-Watch HQ provides technical support and does not direct local on-ground activities.

Please note: Any changes in Seagrass monitoring dates, please advise Seagrass-Watch HQ.



The use of Permanent Transects for monitoring, is a strategy developed by Seagrass-Watch and is commonly used in representative inter tidal meadows larger than 50m x 50m (e.g. 5.5 hectares).

A sentinel site (Permanent Transect sites) is 50m x 50m area within a homogeneous section of meadow. At each site, three parallel 50m transects (each 25m apart) are established.  We advocate, “permanently” marking the site using a GPS to record points at the start and end of each transect.  If you must physically mark the site,  generally only the middle transect is permanently pegged/marked.

The location of sites is recorded by GPS. The seagrass along each transect are sampled by visual observation. At each transect, eleven quadrats are sampled (1 quadrat every 5m), every sampling event. All quadrats sampled are photographed to ensure standardisation/calibration of observers and to provide a permanent record.

Lay out and peg down the three 50 transects parallel to each other, 25m apart and orientated perpendicular to shore (heading out to sea or deeper water). Within each of the quadrats placed for sampling, complete the following steps:


  • Step 1. Take a Photograph of the quadrat
  • Step 2. Describe sediment composition
  • Step 3. Describe other features and ID/count of macrofauna
  • Step 4. Estimate seagrass percent cover
  • Step 5. Estimate seagrass species composition
  • Step 6. Measure canopy height (cm)
  • Step 7. Estimate algae percent cover
  • Step 8. Estimate epiphyte percent cover
  • Step 9. Voucher specimen if required
  • Step 10. Move to next quadrat
  • Step 11. Completion of monitoring
  • Photographs are taken at the every quadrat (0m-50m) along each transect.
  • First place the photo quadrat labeller beside the quadrat with the correct code on it.
  • Take the photograph from an angle as vertical as possible, which includes the entire quadrat frame, quadrat label and tape measure. Try to avoid having any shadows or patches of reflection off any water in the field of view. Tick the photo taken box on the datasheet for that quadrat. Please note: Camera should be set at the highest quality.
  • To assess the sediment, dig your fingers into the top centimetre of the substrate and feel the texture.
  • Describe the sediment, by noting the grain size in order of dominance (e.g., Sand, Fine sand, Fine sand/Mud).
  • Please do not use descriptors like Sandymud, SandyMuddy, Muddysand etc
  • Note and count any other features which may be of interest (eg. number of shellfish, sea cucumbers, sea urchins, evidence of turtle feeding), within the comments column.
  • Count or estimate as best you can. Please do not use > or < symbols.
  • If more than 50% of the quadrat is covered by water, measure and record the water depth in cm.
  • Looking down on the quadrat from above, estimate the total percentage of the seabed (substrate) within the quadrat covered by seagrass. – use the percent cover photo standards as a guide.
  • When estimating cover, estimate the footprint/shadow provided by the seagrass shoots
  • Always use the percent cover photo standards (calibration sheets) as your guide
  • Estimate cover as accurate as possible, e.g. 27%, 61%
  • Identify the species of seagrass within the quadrat and determine the percent contribution of each species to the cover.
  • When determining species composition for two or more species, always start with the least dominant.
  • Use seagrass species identification keys provided.
  • Use more than 1 feature to identify the species
  • Total composition must equal 100%
  • Measure canopy height of the dominant strap leaved species ignoring the tallest 20% of leaves.
  • Measure from the sediment to the leaf tip of at least 3 mature leaf blades (strap leaved species).
  • Write the 3 measures (cm) on the datasheet.
  • Estimate % cover of algae in the quadrat.
  • Algae are seaweeds that are not attached to seagrass but may cover or overlie the seagrass blades.
  • Malcroalgae percentage cover is independent of seagrass cover, for example, you can have 100% seagrass and 100% algae (drift).
  • Use “Algal percentage cover photo guide”.
  • Epiphytes are algae attached to seagrass blades and often give the blade a furry appearance.
  • First estimate how much of the blade surface is covered, and then how many of the blades in the quadat are covered (e.g., if 20% of the blades are each 50% covered by epiphytes, then quadrat epiphyte cover is 10%).
  • Do not include epifauna with epiphytes. Epifauna are sessile animals attached to seagrass blades – please record % cover of epifauna in the comments or an unused/blank column – do not add to epiphyte cover.
  • Use the epiphyte matrix to help you in the field. (DOWNLOAD: Epiphyte_matrix.pdf)
      • Voucher specimens are only required if:
        • establishing monitoring in a new region; a new seagrass species is present;
        • or if you are unsure of the seagrass identification.
      • Seagrass samples should be placed inside a labelled plastic bag with seawater and a waterproof label.
      • Select a representative specimen of the species and ensure that you have all the plant part including the rhizomes and roots.
      • Collect plants with fruits and flowers structures if possible.
  • Repeat steps 1 to 8 for the remaining 32 quadrats
  • Check data sheets are filled in fully.
    • Ensure the full names of all observers (last name and first name), the date and site/quadrat details are clearly recorded on the datasheet.
    • Also record the number of other observers assisting.
    • Also record the GPS positions of the end of each transect.
  • Remove equipment from site
    • Remove all non-permanent pegs and roll up the tape measures. If the tape measures are covered in sand or mud, roll them back up in water.
  • Wash & pack gear
    • Rinse all tapes, pegs and quadrats with freshwater and let them dry.Review supplies for next quarterly sampling and request new materials
  • Store gear for next quarterly sampling
  • Press any voucher seagrass specimens if collected
  • Submit your Data to Seagrass-Watch HQ


A summary

 A visual presentation on basic steps to follow. 

For more detail, please refer to the Seagrass-Watch monitoring Manual

data entry & submission


Once you have monitored your Seagrass-Watch site, you can now enter the data collected into a downloadable Microsoft Excel spreadsheet and submit it via email to

  • Step 1. Select your seagrass geographic bioregion
  • Step 2. Save the spreadsheet file to your computer
  • Step 3. Select the appropriate worksheet
  • Step 4. Enter Observers/Date/Time etc
  • Step 5. Enter Quadrat Observations
  • Step 6. Repeat Steps
  • Step 7. Submit Data to Seagrass-Watch HQ
  • More Detail on Data Entry

Select your seagrass geographic bioregion from the image above, and download the relevant web data entry spreadsheet

  • Region 1: Temperate North Atlantic (North Carolina, USA to Portugal)
  • Region 2: Tropical Atlantic (including the Caribbean Sea, Gulf of Mexico, Bermuda, the Bahamas, and both tropical coasts of the Atlantic)
  • Region 3:Mediterranean (including the Mediterranean Sea, the Black, Caspian and Aral Seas and northwest Africa)
  • Region 4: Temperate North Pacific (Korea to Baja, Mexico)
  • Region 5: Tropical Indo-Pacific (East Africa, south Asia and tropical Australia to the eastern Pacific)
  • Region 6:Temperate Southern Oceans (New Zealand and temperate Australia, South America, and South Africa)
  • Save the spreadsheet file to your computer before you begin data entry. We suggest changing the file name to the site code and the sampling date.
    • For example, if the site was Burrum Heads 1, and it was sampled on 09 February 2020 then the filename would be "BH1_09Feb20.xls"
  • The spreadsheets are a similar layout to the standard datasheets.
  • Each transect has it's own worksheet.
  • To select the appropriate worksheet, click on the tab at the bottom

  • To enter data, select each cell with your mouse.
  • You can jump between cells by using the TAB button on your keyboard.
  1. First enter the FULL NAME (First and Last name) of the observers and the sampling date.
  2. Enter the location and site code.
    • For the above example, the location is "Burrum Heads" and the site code is "BH1".
  3. Enter the time you started sampling the transect and the time you finished. Times are entered at 24 hr with the hour separated from the minutes by a colon.
    • For example. if the time was half past one in the afternoon, the time entered would be "13:30".
  4. If you had a GPS (Global Positioning System) at the monitoring site, the latitude and longitude of the transect start

Enter the data for each quadrat

  • Sediment: enter by the dominant grain size first, separating sediment categories by a forward slash. For example, if the quadrat was predominantly mud with some sand, then the data would be entered as "Mud/Sand".  Please do not use abbreviations "M/S" when entering into the spreadsheet.
  • Comments: Enter information (including counts) of any features which may be of interest. For example, "sea cucumbers (x2), sea urchin (x1), evidence of turtle cropping"
  • Photograph: type in "True" if you took a photo of the quadrat
  • % cover: enter the total percent cover of seagrass within the quadrat
  • % cover by species: enter the percentage cover that each species contributes to the total cover. For Species ID
      • CR = Cymodocea rotundata
      • CS = Cymodocea serrulata
      • EA =Enhalus acoroides
      • HC = Halophila capricorni
      • HD = Halophila decipiens
      • HM = Halophila minor
      • HO = Halophila ovalis
      • HP = Halodule pinifolia
      • HS = Halophila spinulosa
      • HT = Halophila tricostata
      • HU = Halodule uninervis
      • SI = Syringodium isoetifolium
      • TC = Thalassodendron ciliatum
      • TH = Thalassia hemprichii
      • ZC = Zostera capricorni
    • Canopy: enter the three canopy heights of the dominant strap leaf species (the average will calculate automatically)

    • % Algae: enter the percent cover of maco-algae in the quadrat. Macro-algae are seaweeds that are not attached to seagrass leaves and may even overlie the seagrass shoots. The combined seagrass and algae cover may be greater than 100%.

    • Epi %: Enter the percentage cover of epiphytes on the total seagrass leaves. Download Epiphyte_matrix

  • Enter the latitude and longitude of the transect finish

  • Enter any general comments about the transect or site

  • Repeat steps 5 to 10 for the remaining transects

  • Ensure your file is securely saved

At the completion of each monitoring event, as part of Seagrass-Watch data submission and QAQC, the following must be submitted to Seagrass-Watch HQ:

  • Original datasheets: we recommend you make a copy for yourself before posting
  • CD containing (can also be submitted via yousendit/Dropbox etc):
    • MS excel spread sheet (completed): Click Here
    • Photo Quadrats (highest quality possible for camera. Do not resize). Please note, we require photo quadrats to be taken at every quadrat (0m-50m) along each transect.
    • Site & people photos, if taken (highest quality possible for camera.)
  • Voucher press specimens if collected for identification


Original datasheets, Photos ( if not sent via dropbox), Herbarium press ( if collected)

Seagrass-Watch HQ
PO Box 4
Clifton Beach, QLD 4879

For data submission checklist: Click here

For More information on Data Entry : Click here

QAQC & proprietorship


data ownership & property

All raw data collected in the Seagrass-Watch program is the property of the individual/group/institution (principal) who collected it, and Seagrass-Watch HQ is custodian.

When a Principal (data collector) submits data to Seagrass-Watch HQ, it does so under the proviso that Seagrass-Watch HQ can conduct a data quality assessment as part of the Seagrass-Watch program’s QAQC protocols and that the validated data is available for condition and trend reporting. Copies of raw data are provided to third parties only when permission from the principal is provided.

Ownership of data within the Seagrass-Watch program is determined by mutual agreement based on who is collecting the raw data, whether the data undergoes a quality assessment as part of Seagrass-Watch QAQC protocols and the funding sources that support the monitoring.

  • Ownership (intellectual property rights) of the Raw Data lies with the Principal (data collector). Seagrass-Watch is custodian of the Raw Data.
  • Ownership (intellectual property rights) of the Validated Data is shared between the Principal and Seagrass-Watch Ltd.

All data interpretation is conducted by Seagrass-Watch HQ. This ensures that the interpretation of data is consistent, unbiased and of scientific merit. Seagrass-Watch HQ also encourages peer review and assessment of published results.

high quality data

quality assurance/quality control

Seagrass-Watch HQ also ensures the QAQC protocols for the program are followed and that the program is producing data of high quality, ensuring time and resources are not wasted. Quality assurance refers to the management system by which data is collected, organised, documented and evaluated. Quality control refers to the technical means by which error is controlled.

The five indicators of QAQC that the program uses are:

  • Precision: This is the degree of agreement among repeated measurements. This is controlled by conducting scientific training & using calibration sheets.
  • Accuracy: This measures how close results are to a true or expected value. To do this the program requests voucher specimens of seagrasses, conducts refresher scientific training & requires observers to make photographic records (ie 27% quadrats sampled are photographed)
  • Representativeness is the extent to which measurements actually represent the whole population at the time an observation was made. In the program, this is controlled by choosing sites which are representative of the location.
  • Completeness is the comparison between the amount of valid, or useable, data originally planned to collect, versus how much was collected. This is ensured by employing standardised scientific methods (developed in consultation with community volunteers) which are simple and easy to use.
  • Comparability is the extent to which data can be compared between sample locations or periods of time within a project or between projects. This is ensured by using standardised methods and calibration sheets and conducting regular refresher scientific training.