Seahorses Translocation Plan
1. Pre-Translocation Survey
Prior to the translocation, pre-translocation monitoring will be
undertaken at the impact area at Lung Mei and its 50m buffer zone as well as
the Ting Kok East reception site (Figure 1 & 2)
at least one month before the commencement of marine construction works. Should
any changes in circumstances be identified during the monitoring (e.g.
identification of seahorse species other than Hippocampus kuda (H. kuda) that would require to be
translocated, absence of the concerned seahorse species at the reception site), the ET shall revise the translocation
procedures for approval by the IEC before implementation of the translocation
exercise. Species other than H. kuda will also be translocated if being identified
during the pre-translocation survey. If concerned seahorse species is absent at
the reception site, efforts on the pre-translocation survey at the reception
site will be doubled. Divers will dive in a zigzag-like survey route to search
for the target seahorse species.
(a)
Intertidal Survey
Intertidal survey for seahorses will be undertaken by active search at
the impact area at Lung Mei and its 50m buffer zone as well as the reception
site at Ting Kok East. Active searches of seahorses will
be conducted at each site during both day and night time covering the high tide
only (>1.5 m CD), and thus a total of two active search surveys will be
undertaken at each site.
The active search will cover the intertidal and subtidal zones of
approximately 50 m ¡Ñ 200 m (Figures 1 and 2). Direct observations and active
search of seahorses will be conducted in all major habitat/substrate types and
in potential hiding places such as among litter/debris, inside holes/crevices
and under cobbles/boulders. Hand-netting will be used to collect seahorses for data collection such as Torso length and
sign of injury. Head light and hand torch will be used during the night time surveys.
The effort of searching at each site will be standardized to facilitate
comparison of occurrence of seahorse using the number per standard unit effort
approach (i.e. number of man-hours). A total of six man hours will be spent on
each day survey and night survey. Each day/night survey will be conducted in two days (i.e., 3-man hours day survey and 3-man hours night survey per day). The actual
man-hours spent during each survey will be recorded.
(b)
Subtidal Dive Survey
Standard Underwater Visual Census (UVC) surveys will be conducted at the
impact area at Lung Mei and its 50 m buffer zone as well as the reception site
at Ting Kok East. Four subtidal dive surveys will be
conducted at each site, two in day time and two in night time. During the
survey, marker buoys will be deployed to indicate the four corners of the
targeted survey area (Refer to Figures 1 and 2 for the survey area). GPS
readings of the four corners will be recorded. UVC will be performed on belt
transects of 5 m width covering the whole survey area. UVC surveys will be
performed at least 10 minutes after deployment of the buoys and transects. For
night time surveys, only underwater qualitative surveys within the survey area will
be performed. Four man-hours will be spent for each day survey and night survey,
and the actual man-hour spent will be timed and recorded. At each site (Lung Mei and Ting Kok East), the two day/night surveys will be conducted in two
separate days (i.e., 4-man hours day survey and 4-man
hours night survey per day). The
survey effort at Ting Kok East will be doubled (i.e.
extra 2 day surveys and 2 night surveys) if no seahorse is found during the
first pre-translocation survey at Ting Kok East, in
order to increase the probability to find seahorses at the reception site and
obtain baseline data about the original seahorse population.
Once a seahorse is found during the intertidal survey or subtidal dive
survey, focusing survey for additional seahorses will be conducted by searching
in increasing concentric circles of 10 m interval within an area of 50 m from
the spotted individual.
(c)
Data Collection
When a seahorse is found during the survey, the following data will be
recorded:
l Species;
l Sex;
l Reproductive
status;
l Torso length (Figure 5) to nearest 0.5 cm (Refer to
Section 2(b) precautionary measures for measurement);
l Sighting
location, depth and holdfast;
l Proximity to the
nearest seahorse; and
l Sign of stress
or injury.
Four to six SCUBA
divers will be parallel to each other and dive in a zic-zac
route (Figure 3 and 4) along the survey areas to locate any seahorses
encountered during each dive survey. All seahorses will be released to their
natural habitat after data collection. Specimens will be handled with care to
reduce disturbance to seahorses as low as reasonably practicable. At least two
photos, comprising both side profile of the seahorse and close-up of the side
profile of the head, will be taken. Video footage will also be taken for each
individual countered. Sample of the monitoring
sheet for data recording is shown in Appendix B.
Timing:
Two-days survey of at least 28 man hours at each site (i.e. 28
man hours for Lung Mei and 28 man hours at Ting Kok
East)
Intertidal Survey
Survey time: At
least 12 man hours, 6 man hours during day and night time respectively for each
survey at each site
Subtidal Survey
Survey time: At
least 16 man hours, 8 man hours during day and night time respectively for each
survey at each site
The translocation area will be updated base on the
pre-translocation monitoring results.
2.
Seahorses Translocation
(a) Capture of Target Seahorse Species
Given that silt curtain will be in place at Lung Mei Project Site before
conducting any searches for seahorses in the area, subtidal and intertidal surveys within the
impact area in Lung Mei in the depth range of 0.5m to -6m CD by SCUBA diving
(see attached Figure 1 the area within the Site Boundary) will be conducted by the translocation team
until saturation is reached (when additional seahorse sightings per unit search
effort reaches zero). At least three dive surveys will be conducted.
The total search effort will not be less than 28 man hours (16 man hours day
survey/12 man hours night survey). The day/night survey will be conducted in
two days (i.e., 8-man hours day survey and 6-man hours
night survey per day). If pregnant seahorse is found OR if no
seahorse is found and captured during the first 28 man-hours, the search effort
will be doubled (i.e. total 56-man hours) in order to search the breeding
partner and any additional seahorses in the area.
Both day and night dives survey will be conducted when the subtidal zone is
submerged underwater. For day time search, it will commence in early morning to
increase the chance of finding breeding pairs in the close proximity which will
be translocated together. Hand torch will be used for searching during the
night time translocation.
During the active search, marker buoys will be deployed to indicate the
vertices of the target search area. GPS readings of the marker buoys will be
recorded.
When a seahorse is encountered, the translocation team member will
unhook the tip of its tail until it releases its grasp. Details of the seahorse
will then be recorded. A pro forma of the translocation record is shown in
Appendix A.
Once a seahorse is found, active search will be conducted within an area
of 50m from the spotted individual by searching in increasing concentric
circles of 10m interval in order to look for additional seahorses.
Photos and video footage will be taken for each individual encountered.
At least two photos, comprising both side profile of the seahorse and close-up
of the side profile of the head, will be taken. The side profile of seahorse will
include a ruler for scale reference with facial spines and the coronet being
clearly showed on the photo. The close-up of the side profile of the head will
clearly show the facial spines, especially check spines, and coronet. The
encountered individual(s) will be tagged following Section 2(f).
The seahorse will be captured by hand and placed into a Kordan Breathable Bag, unless otherwise approved by the
IEC. Inside the bag, appropriate substrates/ holdfasts (e.g. PVC rod, plastic
plant or substrate that the seahorse is found attached to) will be provided to
the seahorses. The Kordon Breathable Bag with the
captured seashore will be taken to the surface at a slow ascending rate. The
bag will be tied off at the water surface.
Each Kordon Breathable Bag will only keep one
captured seahorse.
After leaving water, the Kordon
Breathable Bags with the captured seahorses will be placed in robust containers
with continuous aeration. Individuals of different seahorse species will not be placed in the
same bag or container unless species are known
to be compatible with each other. The Kordon
Breathable Bags will not be in contact with each other in the container.
(b) Handling, Transportation of Captured Seahorse
Each captured seahorse will be translocated to the reception site at
Ting Kok East immediately during the same day of capture. The
container with the Kordon Breathable Bags will be
transported to Ting Kok East on-land, or by marine
vessel. Care will be taken during the whole handling process in order to ensure
no harm and/or sedation to the captured individuals during transport, with the
following precautionary measures to be implemented:
l If more than one
seahorse were captured, at least two seahorses (in two separate Kordon Breathable Bags) will be placed together in a
container, only if species are known to be compatible with one
another
l Empty inflated bags will be put in the
container to ensure the Kordon Breathable Bags do not
move within the container during transportation.
l The containers will
be secured properly to the vehicle/vessel to avoid any movement during
transportation.
l The containers will
be properly covered to avoid overheating of sea water, particularly during
daytime. Heat/ cool packs will be used to maintain the temperature of seawater
during transit.
l Depending on the
length of time it takes to capture and relocate the captured seahorses,
containers will be checked at 30-minute intervals or less and such checking will
be recorded properly in the pro forma of translocation record shown in Appendix
A.
The following precautionary measures will be implemented when handling
the seahorse during the translocation process:
l When capturing
the seahorse from the holdfast, the tail of the seahorse will be unhook and the
seahorse will be removed from the holdfast after it releases its grasp;
l When measuring
the length of the seahorse, the seahorse will be held in one hand with its tail
curled around a temporary holdfast such as little finger of the translocation
team member. The trunk of the seahorse will be held between the thumb and
forefinger. The length of the seahorse will then be measured with a caliper held in the other hand, while the seahorse lies
passively.
Translocation might be expedited by dividing the
translocation team into two sub-teams: one for capturing seahorses at Lung Mei,
one for transport and release of the seahorses at Ting Kok
East
(c) Release of Captured Seahorse
The target release area will be marked by marker buoys with the GPS
location recorded. At the reception site, the captured seahorses will be
released into the habitat type and depth at which they are found.
The information for the release process will be in the pro forma of
translocation record as shown in Appendix A. The following precautionary
measures will be implemented when releasing the captured seahorse at the reception
site:
l Only two
seahorses will be released at a time, with breeding pair released together. An
hour interval will be allowed for between consecutive release events.
l Except for
individuals of the putative breeding pair, the captured individuals will be
released at different locations of at least 50 m separation distance.
l Breeding pairs,
if any, will be released together in the same area.
The released seahorses will be monitored underwater
from a distance of 1-2 m until they settle onto holdfasts.
(d) Seahorse in Potentially Sensitive Stage
Pregnant, breeding or injured seahorses found at the search area are
considered as in potentially sensitive stage. The following precautionary
measures will be implemented for seahorses at sensitive stage:
l Pregnant
seahorses will be handled with care to ensure that they settle to a holdfast on
release at the reception site.
l The potential
breeding pairs will be kept together when captured, transported and released at
the reception site.
l If breeding pair
is exhibiting breeding/ courting behaviour, they will be left undisturbed and
the breeding pair will only be collected for translocation after completion of
their breeding/ courting behaviour.
l Seahorses that
are injured will be translocated if they are found at the search area.
Seahorses that become sick or injured (with
noticeable infection or hurt) will receive veterinary treatment as soon as possible. A record of any
such occurrences will be kept. The sick or injured
seahorses will be transported to Simon F. S. Li Marine Science Laboratory, The Chinese University of Hong
Kong or Aquatic Laboratory, The Hong Kong Baptist University. The sick or injured seahorse will be
monitored daily (may apply medication if needed) until it is fully recovered.
Recovered seahorses will be transported back to Ting Kok
East immediately.
(e) Translocation Record
Proper records will be maintained by the translocation team during the
translocation exercise (see Appendix A).
The qualified Fish Expert will be responsible for
checking the record against the translocation measures to audit the proper
implementation of the translocation exercise. The records will then be
certified as complying with the translocation plan by the IEC. Should
non-compliance of the translocation procedure be observed, the qualified Fish
Expert will notify the IEC within 24 hours and be responsible for proposing
corrective actions which will be agreed by the IEC and implemented by the
translocation team during the next translocation day. The qualified Fish Expert
and the IEC will check the proper implementation of the corrective actions by
the translocation team.
(f) Seahorse Tagging
The captured seahorses from Lung Mei before released into the reception
site of Ting Kok East will be tagged. The tags will
allow differentiation of the translocated seahorse from Lung Mei and the
seahorse(s) originally found at Ting Kok East.
(i)
Collar Tags (Preferred)*
A non-invasive external tagging technique involving collar
tags (oval PVC disc (3X5mm) with a 3-digit number on one side, Figure 6) will
be attached around the neck of a seahorse with cord (Figure 7), to provide
individual identification. (seahorse has to be over 4cm in length for tagging). Reference will be made to the Project Seahorse Technical
Report No. 6 ¡V Selected Techniques for Tagging Seahorse as shown in Appendix C.
This tagging method has been applied to various
seahorse species worldwide, including the U.K., South Africa, Brazil and the
Philippines. It was found to be a non-invasive and a successful tagging method
by Project Seahorse, (Morgan & Martin-Smith, 2004; Morgan & Bull,
2005), as proven by a study by Seahorse Trust in which a tagged individual was
deliberately kept in an obstacle-ridden captive environment for 4 years.
In 2013, this collar tagging method was adopted
by Ocean Park Conservation Foundation at its Seahorse Survey Project to tag
local seahorse species H. kuda
and successfully used in the field.
Timing:
Lung Mei
Survey time: At least 28
man-hours including day and night diving (survey time will be doubled - 56
hours, if pregnant seahorses were found during the translocation survey)
Frequency: One
*Reasons for using Collar Tag over VIFE methods:
1.
Collar
Tag is non-invasive but VIFE is an invasive method
2.
Risk
of infection and increased mortality when using VIFE
3.
Collar
Tag can last for years (4 years) but VIFE can only last for 6 months to 1 year
4.
Collar
Tag has been using in Hong Kong for tagging local H. kuda by OPCF
5. No previous experiences in using VIFE in Hong Kong as
well as H. kuda,
pilot study of using VIFE in Hong Kong should be needed
3.
Post-Translocation Monitoring at Ting Kok East
After translocation is completed, the reception site will be monitored
regularly by the qualified fish expert over a period of one year, following the
same survey methodology for the pre-translocation monitoring.
The following information will be provided in the post-translocation
monitoring report:
l Seahorse species
recorded;
l Seahorse
abundance;
l Size structure;
l Sex ratio;
l Population
estimates through mark/ recapture of the tagged seashores;
l Observation of
any temporal / seasonal fluctuations;
l Reproductive
status;
l Habitat
preferences; and
l Presence of
putative pairs.
To
evaluate the success of the translocation exercise, the population of seahorse
at the reception site of Ting Kok East, which would
include the original seahorse individuals found at the reception site and the
translocated individuals from Lung Mei, will be estimated regularly in order to
determine any changes to the seahorse population. Translocation exercise will
be evaluated as successful if (i) more than 80% of
the translocated seahorses were recorded alive for at least one time during the
first month of the post-translocation monitoring (i.e. during the daily and
weekly monitoring in the first month), and (ii) more than 50% of the
translocated seahorses were recorded alive for at least one time during the
monthly post-translocation monitoring, and (iii) no significant decline in the
original seahorse population at Ting Kok East is
observed at the end of the 1-year post-translocation monitoring period. In
addition to the population trend of post-translocation, the metrics presented
in the table below will also be assessed and considered for the evaluation. The
evaluation will be presented in the Post-translocation Monitoring Report. The evaluation
of success in achieving objective of translocation mentioned above should be
fine-tuned for a pragmatic approach based on the records of pre- and post-
translocation monitoring and the actual result of the seahorses translocation
exercise, and shall be subject to the agreement of EPD and AFCD.
Item No. |
Metrics |
1 |
Any translocated individuals observed? |
2 |
Any individuals observed injured or under sign of stress? |
3 |
Any breeding behaviour observed? |
4 |
Any pregnant seahorses observed? |
5 |
Any juvenile seahorses observed? |
6 |
Any change in habitat quality? |
The Post-translocation Monitoring Report will be submitted monthly and will
present findings of all seahorse surveys undertaken in the reporting month.
Each monthly Post-translocation Monitoring Report will be submitted within two
weeks of completion of the last seahorse survey in the reporting month.
Plan of post-translocation monitoring
Option
1 ¡V Translocated seahorse(s) is/are recorded at first week¡¦s daily monitoring
Timing
(i) First Week
(Daily Survey):
Survey time: At
least 28 man-hours, 14 man hours during day and night time respectively for
each survey
Frequency:
Seven
(ii)
Second
to Fourth Week (Weekly Survey):
Survey time: At
least 28 man-hours, 14 man hours during day and night time respectively for
each survey
Frequency: Three
(iii)
Second
to Twelve Month (Monthly Survey):
Survey time: At
least 28 man-hours, 14 man hours during day and night time respectively for
each survey
Frequency: Eleven
Option
2 ¡V NO Seahorses recorded at first week¡¦s daily monitoring
Timing
(i)
First
Week (Daily Survey):
Survey time: At least 28 man-hours, 14 man hours during day and
night time respectively for each survey
Frequency:
Seven
(ii)
Second
to Fourth Week (Three Time per Week):
Survey time: At
least 28 man-hours, 14 man hours during day and night time respectively for
each survey
Frequency: Nine
(iii)
Second
to Fourth Months (Weekly Survey):
Survey time: At
least 28 man-hours, 14 man hours during day and night time respectively for
each survey
Frequency: Thirteen
(iv)
Fifth
to Twelve Months (Monthly Survey):
Survey time: At
least 28 man-hours, 14 man hours during day and night time respectively for
each survey
Frequency: Eight
(monthly survey until one year
post-translocation)
Remarks:
The monitoring plan mentioned above is an ideal approach and should be
fine-tuned for a pragmatic approach based on the records of pre- and post- translocation
monitoring and actual result of the seahorses translocation exercise. Any updated plan shall be subject to the
agreement of EPD and AFCD.
4. Post-Construction Monitoring at Lung Mei
Post-construction monitoring will be undertaken at
the installed shark net during the maintenance period of the Project. The shark
net will be inspected by the qualified fish expert using SCUBA to search for
the presence of any seahorse species. Data collection procedure as stated in Section
1(c) will be followed. Monitoring will commence three months after installation
of the shark net. Quarterly monitoring will be undertaken until the end of the
maintenance period of the Contract. A Quarterly Post-construction Monitoring
Report will be submitted within two weeks after the completion of the quarterly
monitoring survey to present ecological information of the seahorse found, if
any, along the shark net.
Timing
Survey time: At
least 28 man-hours including day and night diving
Frequency: To
be determined (quarterly monitoring until completion of the maintenance period
of the Contract)
5. Seahorse Translocation Programme
The actual
translocation schedule shall be recorded separately in the monthly EM&A
report.
Figure 1. Proposed Survey Area of Lung Mei
Figure 2. Survey Areas for Ting Kok East
Figure 3. Proposed Dive Survey Route at Lung Mei
Figure 4. Proposed Dive Survey Route at Ting Kook East
Figure 5.
Torso Length Measurement (Extracted from ¡§The life history and ecology of
seahorses in the Philippines)
Figure 6. Collar Tags
Figure 7. Seahorses with
Collar Tag (Photos from OPCF)
Survey Time Summary
Pre-translocation Survey |
Man-hours |
Frequency |
Intertidal + Subtidal |
|
|
Lung Mei |
28* |
1 |
Ting Kok
East |
28* |
1 |
Extra Survey at Ting Kok East (reception site) if no seahorse was found in the
first pre-translocation survey |
28* |
1 |
Seahorses Translocation |
|
|
Subtidal |
|
|
Lung Mei |
28* |
1 |
Extra Survey at Lung Mei if pregnant
seahorses were found OR if no seahorse was found during the first 28
man-hours search |
28* |
1 |
Post Translocation Survey |
|
|
Option 1 (seahorse found at the first week) |
|
|
First One Week (Daily Survey) |
|
|
Ting Kok
East |
28 |
7 |
Second to Fourth Week (Weekly Survey) |
||
Ting Kok
East |
28 |
3 |
Second
Month to Twelve Month (Monthly Survey) |
||
Ting Kok East |
28 |
11 |
Option 2 (seahorses were absence at the first week) |
|
|
First One Week (Daily Survey) |
|
|
Ting Kok East |
28 |
7 |
Second Week to Fourth Week (3 times per week) |
|
|
Ting
Kok East |
28 |
9 |
Second Month to Fourth Month (Weekly Survey) |
|
|
Ting
Kok East |
28 |
13 |
Fifth Month to Twelve Month (Monthly Survey) |
|
|
Ting Kok
East |
28 |
8 |
Post-Construction
Monitoring |
|
|
Quarterly to completion to the maintenance
period |
||
Lung Mei (Quarterly Monitoring) |
28 |
TBD |
Remarks:
1.
Man-hours with asterisk
will be split into two days to increase the probability to relocate the
affected seahorses in Lung Mei project site and set up a more reliable baseline
at Ting Kok East before translocation.
2.
The post translocation
monitoring plan mentioned above is an ideal approach and should be fine-tuned
for a pragmatic approach based on the records of pre- and post-translocation
monitoring and the actual result of the seahorses translocation exercise. Any updated plan shall be subject to the
agreement of EPD and AFCD.
Number and Type of
Manpower and Apparatus Involved Per 28 Man Hours
Type |
Number |
Dive Boat |
1 |
Sampan |
1 |
|