Presentation made at the Sustainable Tourism in Small Island Developing States conference, 23-24 November 2017, Seychelles. A partnership of the Seychelles Sustainable Tourism Foundation, IUCN WCPA Tourism and Protected Areas Specialist Group, University of Seychelles, Paris Tourism Sorbonne (IREST), and Global Sustainable Tourism Council.

1. ASK AND YOU SHALL RECEIVE
REDUCING DIVER IMPACTS ON GUAM’S CORAL
REEFS WITH A CORAL-SAFE DIVING REMINDER
Ashton Williams
& Dr. Laurie Raymundo
University of Guam Marine Laboratory

2. Population: 160,000
Size: 544 km2
Annual Visitors: 1.4 million
Resident divers: 30,000
Visitor divers: 140,000
GUAMGUAM
170,000How can we reduce the impacts of divers on
Guam’s coral reefs?

3. How do divers damage coral?
• Kick and bump corals
• Sit and stand on corals
• Grab corals
• Kick up sand/sediment clouds
• Intentionally damage corals
• Use sunscreens with chemicals
that harm corals

4. Why do divers damage coral?
• Failure to streamline
• Too close to reef
• Poor buoyancy
control
• Distractions
• Ignorance
How can we reduce the impacts of divers on
Guam’s coral reefs?
What if we reminded divers to practice
“coral-safe diving” before each dive?

5. Watch your buoyancy, and be careful to avoid
touching, bumping, or kicking the corals!

6. “Watch your buoyancy, and be
careful not to touch, kick, or
step on the corals!”
Photo: Mike Schuck
5-minute observation
• Substrate touched
• Body part used
• Intention
• Damage
• Camera & glove use
• Buoyancy control
Questionnaire
• Demographic data
• Socio-economic data
• Diving experience and
training
• Diving-related beliefs
and opinions

7. Finding #1: “Coral-safe diving reminder” works!
0
0,5
1
1,5
2
2,5
3
3,5
4
4,5
5
Reminder No Reminder Reminder No Reminder
#ofContacts
Accidental Contacts Intentional Contacts
Mean contacts per 5-minute observation period
p=1.10E-13 p=1.17E-13
• Kruskal-Wallis
• Highly significant
differences
Simple, easy,
cost-free tool to
reduce diver
impacts on coral
reefs!

8. Finding #2: Cameras & gloves = more reef contact
• Kruskal-Wallis
• Significant
differences
Divers with
gloves and
cameras should
be supervised
more carefully.
0
0,5
1
1,5
2
2,5
3
3,5
4
4,5
5
Camera No
Camera
Gloves No
Gloves
Camera No
Camera
Gloves No
Gloves
#ofcontacts
Accidental Contacts Intentional Contacts
Mean contacts per 5-minute observation period

9. 0
1
2
3
4
5
6
DSLR GoPro Point & Shoot DSLR GoPro Point & Shoot
#ofcontacts
Accidental Contacts Intentional Contacts
Mean contacts per 5-minute observation period
Finding #2: Cameras & gloves = more reef contact
• Kruskal-Wallis
• Significant
differences
Divers with
gloves and
cameras should
be supervised
more carefully.
p=0.003 p=0.003 p=0.002p=0.0004
p=0.01 p=0.0002

10. 0
0,5
1
1,5
2
2,5
3
3,5
4
4,5
5
Guam Visitor Guam Visitor
#ofcontacts
Accidental Contacts Intentional Contacts
Mean contacts per 5-minute observation period
• Kruskal-Wallis
• Significant differences
for accidental
contacts, but not
for intentional
Finding #3: Visitors have more reef contact
• Mann-Whitney
• Significant differences
for both intentional
and accidental contacts
Visiting divers
should be
supervised more
carefully than
resident divers.
p=4.95E-05 p>0.05p=5.19E-06 p=0.013
…but not all equally.

11. 0
1
2
3
4
5
6
Asia North America Guam Asia North America Guam
#ofcontacts
Accidental Contacts Intentional Contacts
Mean contacts per 5-minute observation period
• Kruskal-Wallis
• Significant differences
for accidental
contacts, but not
for intentional
Finding #3: Visitors have more reef contact
• Mann-Whitney
• Significant differences
for both intentional
and accidental contacts
Visiting divers
should be
supervised more
carefully than
resident divers.p=4.95E-05 p>0.05p=5.19E-06 p=0.013
…but not all equally.

12. Additional findings
• Briefing before 1st dive reduces
contact on both dives
• Divers with poor buoyancy control
make more accidental contacts
• Groups of 5 or more divers have
more individual contacts
• Positive correlation between
guide & client contacts
• Number of lifetime dives >
certification level
• Divers are generally self-aware of
skill level and buoyancy control
• Most divers want to know more
about coral reefs

13. Takeaways & Implications
• Reminding divers to practice coral-
friendly diving can reduce diver
impacts on coral reefs
• Some divers should be supervised
more carefully to reduce their impacts
• Diving professionals are willing to help
• Voluntary effort > regulations/laws
• Green Fins materials
• Divers want to learn—let’s help dive
operators teach them!

14. Thank you & si yu'os ma’åse!
• Dr. Laurie Raymundo
• UOG Marine Laboratory
• Micronesian Diver Association
• Guam Visitors Bureau
• NOAA