Time Lapse Video Monitoringof

Manta Ray Bay

Great Barrier Reef Marine ParkAustralia

Thorne Abbott

CoastalZone.com

Great Barrier Reef

Whitsunday Island Chain Hook Island

High use dive & snorkeling site with excellent visibility

and protected anchorage

Manta Ray Bay

Actual Video Monitor Image

Concerns & Conflicts

• Concerns over coral damage from– anchors

– diver fins

– contact by snorkelers

• Fish feeding• Trash & refuse• Water quality

• Number of Moorings– Commercial: more

– Residents: less

• Boat tethering• Dinghy access to beach• Overcrowding during

water activities

Challenge . . .

Design a self-contained monitoring system that could be used at remote locations

in the Great Barrier Reef Marine Park

to enhance sustainable use decision-making

Objectives

Determine appropriate sampling strategies for video

monitoring

Analyze the resolution or clarity of the imagery produced

Calibrate the validity of the data generated

Determine if the results obtained can enhance decision

making

Monitor Equipment

• Camera• wide angle lens

• polarizer

• zoom facility

• Processor• Battery Re-charger• Solar Panel• Battery's

• Monitor Housing• prospecs lens

• telescoping stand

• tripod head

• camera housing

• padlocks, security

• Laptop Computer• Software

• Battery

Monitoring Performance0

1020

30

Nu

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f D

ays

To

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Da

ys

Mo

nit

ore

d

Fa

ile

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• The monitor worked 43% of the time

• 83% of the video samples were ground-truthed by physical observation

• When operational, activity was observed 41% of the time

Video Footage

Vessels172 samples 20 seconds each

Visitors52 samples originally 20 seconds each

Master Tape High Resolution S-VHS Format

12 Data TapesHigh Resolution Hi - 8 Format

Video Camera Monitoring

Results of Sampling StrategyTable 1 : Vessel Excursion Information

RecordingTime

Numberof

Vessels

Number ofExcursions

Numberof

Samples

SamplingPeriod

Commercial Vessels 20:55 6 15 34 %Private Vessels 10:40 18 12 17 %Dinghy’s 6 6Vessel Activity 25:40* 24 33 120 41 %*Visitor Activity 52Total Activity 25:40* 172 41%*No Activity 59%NB .: *Some samples included multiple vessel types at the same time.

Vessel Samples

Number of Visitors"expected"

Size Time

Type Day

Mooring Date

Vessels172 samples 20 seconds each

Vessel Sizes at Moorings

187710N =

Ve s se l S ize s a t M oo rings

all Vessels

MOORING

QueuingNot MooredCBA

SIZ

E in

met

ers

1614121086420

Vessel Patterns Vessels ranged from 3 m to 15 m long

Moored vessels averaged 10 m long

Most private vessels exceeded 10 m

Private vessels visit the bay as often as commercial vessels

Commercial vessels use the bay for twice as long Dinghy’s were often used in the bay

Mooring Times

187710N =

M oo ring Ince ptio n T im e o f D a y

all Vessels

6 = 6:00 AM18 = 6:00 PM

MOORING

QueuingNot MooredCBA

TIM

E o

f Day

18

12

6

.

Length of Stay

576114N =

D ura tio n o f A nc ho rage

by Vessel type

Private YachtPriv. Motor Boat

DinghyDaily Tour Oper.

Comm. Charter

DU

RA

TIO

N in

min

utes

300

200

100

0 .

Mooring Patterns Vessels moored between 10 AM and 4 PM Vessels arriving between 2 PM and 3 PM often

queued or did not use a mooring Average stay was two hours, three hours maximum* Two vessels moored overnight* Vessels that moored, did so within 20 minutes Mooring “C” was used last, least, and for less than

one hour

SCUBA DivingNum be r o f S c uba D ive rs

by Time of Day

TIME

5:003:30

3:002:45

1:551:45

1:201:00

12:4012:20

12:0011:40

11:0510:40

10:20

Num

ber o

f Dive

rs

8

6

4

2

0

Snorkeling

by Time of Day

TIME of Day

5:003:30

3:203:00

2:301:55

1:401:00

12:4012:20

11:4011:05

10:20

Num

ber o

f SNO

RKEL

LER'

s

16

14

12

10

8

6

4

2

0

N u m b e r o f S n o r k e l l e r s

Visitor Patterns

Most activity takes place between 10 AM and 4 PM

Scuba divers visit morning to mid-daySnorkelers visit in the afternoonSubstantially more snorkelers than divers

Visitor Samples

Low Resolution VHS std FormatVisitor Counts by 3 Observers

High Resolution S-VHS FormatVisitor Counts by 4 Observers

19 @ 20 seconds19 @ 10 seconds19 @ 5 seconds19 @ 1 second

19 original samples4 sub-samples per original

14 @ 20 seconds14 @ 10 seconds14 @ 5 seconds14 @ 1 second

30 original samples1, 2, or 3 sub-samples per original

Randomness

Visitors52 samples originally 20 seconds each

Effect of Resolution& Sample Length

P e r c e n t a g e O b s e r v e d t o E x p e c te d

L e n g t h o f S a m p le ( T IM E )

2 0 se conds1 0 se conds5 se conds1 se cond

Pe

rce

nta

ge

Ob

se

rve

d

T a p e F o rm a t

V HS std.

S -V HS

1.0.9.8.7.6.5.4.3.2.1.

Comparison o f Visitor Counts

VHS std. to S-VHS Tape Formats

Accuracy of Observers Estimatesof Visitor Activity

0

20

40

60

80

100

1 5 10 20Length of Recorded Sample

(seconds)

Per

cen

tag

e A

ccu

racy

VHS standard resolution S-VHS high resolution

Methodology

The Method of Monitoring can be» consistent (Chi^2 : p>.05)» accurate (>70%)» using HIGH resolution tape format» and samples 10 seconds or longer

Recommendations• Install a shared commercial mooring

• Update signage in the bay

• Pre-program the micro-processor for sampling

• Upgrade to a 12 volt auto battery power source

• Sampling strategy:

– 15 minute intervals

– from 9 AM to 5 PM

– recordings 10 to 15 seconds in length

Recent Applications

• Time-lapse video monitoring of boat traffic in Missionary Bay and Hinchinbrook Channel, World Heritage Area

• Establish Dugong movement patterns and their interactions with boat traffic.

• 2500 samples collected to date

Opportunities Underway• Web-based remotely controlled panoramic views of

coral reefs and fish for educational purposes

• Monitoring of diseases in coral assemblages

• Monitoring changes in size, volume, and coverage over time at specific sampling locations

• Coral coverage based on video transects

• Measuring the effect of fragmentation on meta population sustainability

• Assessing reef health and viability at various scales

Conclusion

Time lapse video monitoring

provides valuable data

on visitor and vessel patterns of use

assisting managers in designing

sustainable management options

Acknowledgements Great Barrier Reef Marine Park

Authority

Ray Berkelmans

Graeme Inglis

The Coastal Society

CRC Reef Research Centre

Queensland Dept. of Environment & Heritage

James Cook University Dept. of Tropical Environmental Studies & Geography

Thorne Abbott

CoastalZone.com