Assessment of coral reefs damaged due to MV Pazifik ran aground in the Sape Strait using an aerial photography approach and species distribution modeling

1. Assessment of coral reefs damaged due to MV Pazifik ran aground
in the Sape Strait using an aerial photography approach and species
distribution modeling
Ofri Johan1*, Idris2, Fakhrurrozi2, Mikael Prastowo2, Safran Yusri2 and Osten Sianipar3
(1) Balai Riset Budidaya Ikan Hias, Pusat Penelitian Perikanan, Badan Riset dan Sumberdaya Manusia,
Kementerian Kelautan dan Perikanan, Depok, 16436, Indonesia
(2) Indonesian Coral Reef Foundation (TERANGI) Depok 16438, Indonesia
(3)Direktorat Penyelesaian Sengketa Lingkungan Hidup Luar Pengadilan-Kementerian Lingkungan Hidup dan
Kehutanan
INTERNATIONAL SYMPOSIUM ON AQUATIC SCIENCE AND RESOURCES
MANAGEMENT (IS-ARM)
“Highland to Ocean: Biology, Ecology, and Aquatic Resources Management”

2. International Conference of Marine Science (ICMS) 2019 Bogor, 4th September 2019
presentation outline
1. Introduction
2. Purpose
3. Metodologi
4. Result and Discussion
5. Conclusion

3. Scleractinian corals are keystone species of tropical reef ecosystem
provide high complexity of habitat structure support a
high biodiversity.
Coral Reef
INTRODUCTION

4. very good
good
fair
bad
Source: LIPI (2017)
Jumlah
lokasi
Persentase
Very Good Good Fair Bad
Western
Indonesia
435 8,97 22,99 34,71 33,33
Central Indonesia 407 4,91 24,57 43,73 20,8
Eastern
Indonesia
222 4,05 22,07 34,58 39,25
Total Indonesia 1184 6,39 23,40 35,06 35,15
INTRODUCTION

5. • Pollution
• Destructive and overfishing
• Decrease in important Species
• Climate change
• Invasive Species
• Decrease of Important habitat
• Ship Grounding
Causes of Damage to Coral Reefs
INTRODUCTION

6. Objectives :
Assessing the condition of the coral reef ecosystem where the
MV Pazifik depleted :
1. identifying and mapping damage levels of the coral reefs
and
2. identifying affected of coral reefs species
3. to quantify the damaged area of the coral reef

7. International Conference of Marine Science (ICMS) 2019 Bogor, 4th September 2019
Methodology

8. The location of the MV PASIFIK ship ran aground in the Sape Strait, West Nusa Tenggara (GPS
point 08,4881430 S - 119,3377760 E)
Study Site
- The study was
conducted on 4-5
August 2018
- 2 (2 replicate) of station
spreaded in Gili Banta
Island as a ground
check point.

9. The location of the MV PASIFIK ship ran aground in the Sape Strait, West Nusa
Tenggara (GPS point 08,4881430 S - 119,3377760 E)
The survey was performed on 4-5 August 2018.
Point 1
Point 2
Ship grounding location

10. Research Methods
A. Data Collection Technique for coral reef habitat
• Data collection technique for underwater
substrate was done with Underwater Photo
Transect (UPT) (Giyanto, 2012a; Giyanto, 2012b).
• Coral species data collection was carried out
using belt transects and enumeration (English, et
al., 1997), 1 x 50 m each transect. Observation
points were set on non-affected areas (four
transects).

11. Research Methods
B. Aerial Photography
• DJI Phantom 4 drone which begins with planning a
flight path with a flying height of 30, 115, and 221
meters to obtain representative visual data.
• The results of the shooting are processed by
combining all drone photos with a spatial resolution of
4.3 (four point three) centimeters per pixel using the
Agisoft Photoscan software by merging / aligning
photos with each other and creating a mosaic

12. Research Methods
C. Species distribution modelling
• Coral occurrence and environmental data were used as the input for Maxent version
3.4.1 (https://biodiversityinformatics.amnh.org/open_source/maxent/) to model coral
distributions (Phillips 2017).
• Default model parameters were used as they have performed well in other studies and
validated on a wide range of datasets (a convergent threshold of 10-5, maximum
iteration value of 500 and a regularization multiplier of 1) (Phillips and Dudik 2008).
• Threshold feature used was 10 percentile training presence.
• Models were ran with three fold cross validation, where presence locations were split
into training data for model fitting and test data for model evaluation, and then
averaged (Merow et al. 2013)

13. Data Analysis
• Underwater photographic data on each transect were analyzed using CPCe software,
Coral Point Count with Excel extensions (Kohler & Gill, 2006).
• Analysis of the percentage underwater substrate covered are refers to English et al.
(1997) by calculating the percentage category of substrate cover obtained from the
formula:
• Percentage of category cover = (number of i- categories) / (number of random dots) x
100%
Criteria for coral reef health (Zamani and Madduppa, 2011)

14. Data Analysis.....
Area of ​​Damage to Coral Habitat
• Aerial photography with drones is used as the basis for mapping damage at a
standard scale using the length of the ship as a reference.
• Analysed of the aerial photographs with the commercial software Agisoft
Photoscan (http://www.agisoft.com), which uses advanced SfM and
multiview stereo algorithms to construct an ortho-photomosaic and a 3D
point cloud from overlapping photographs.
• Digitization is carried out around the white color of the wrecked ship so that
the area of ​​damage is obtained.
• The area of ​​habitat damage caused by shipwrecks was calculated using Image
J Ver. 1.51j8.

15. Result and Discussion
Hard Coral Cover and Diversity at The Ground Check Point
13%
0%
23%
62%
0%
0%
1%
0%
1%
CORAL (HC)
RECENT DEAD CORAL (DC)
DEAD CORAL WITH ALGAE
(DCA)
SOFT CORAL (SC)
SPONGE (SP)
FLESHY SEAWEED (FS)
OTHER BIOTA (OT)
RUBBLE (R)

16. Result and Discussion..... Coral Genera Distribution Model
• it was found 35 and 55 genera at
the control location (transect 1
and transect 2)
• at the ship aground only 3-5
genera were found that were
possible to live.
• Therefore, it can be said that the
location of the ship aground it’s
to be a habitat for several genera
of hard corals

17. Digitizing the affected
area in the aerial photo,
the total area of ​​damage
due to the ship aground is
613.63 meter square.
Damage Area
Extent of damage area
Result and Discussion.....

18. Conclusion
Some of the conclusions obtained from the results of this study:
1. Hard coral species that were found at the observation location were 38
species of hard corals from 26 genera that belong to the Anthozoa class and
1 genus to the Hydrozoa class.
2. The condition of the coral reefs at ground check point has an average
percentage of hard coral cover of 13.36% which is in the badly damaged
category.
3. At the ship aground only 3-5 genera were found that were possible to
live.
4. The location of the ship aground it’s to be a habitat for several genera of
hard corals
5. The total area of ​​damage caused by the ship aground is 613.63 meter
square.

19. Ackowledgment
The author conveys their gratitude to the Directorate of Environmental Dispute
Resolution and Director General of Law Enforcement- Ministry of Environment
and Forestry. Indonesia Coral Reef Foundation (TERANGI) for the equipment
and literature support.

20. Thank You