Ecosystem Threats: Ecosystem Threats: What the fishing community - - PowerPoint PPT Presentation

ecosystem threats ecosystem threats what the fishing
SMART_READER_LITE
LIVE PREVIEW

Ecosystem Threats: Ecosystem Threats: What the fishing community - - PowerPoint PPT Presentation

Ecosystem Threats: Ecosystem Threats: What the fishing community can do to ensure a sustainable future do to ensure a sustainable future Val Brown JIMAR Coral Reef Ecologist JIMAR Coral Reef Ecologist NOAA Fisheries Pacific Islands Regional


slide-1
SLIDE 1

Ecosystem Threats: Ecosystem Threats: What the fishing community can do to ensure a sustainable future do to ensure a sustainable future

Val Brown JIMAR Coral Reef Ecologist JIMAR Coral Reef Ecologist NOAA Fisheries Pacific Islands Regional Office March 18, 2010 Regional Ecosystem Advisory Committee

slide-2
SLIDE 2

Overview Overview

  • Reef Ecosystem Interactions 101

Reef Ecosystem Interactions 101

  • Ecosystem Threats

R ili t R f

  • Resilient Reefs
  • Paths to Resiliency
slide-3
SLIDE 3

Simplified View of a Reef Simplified View of a Reef

Fish, , Invertebrates, Turtles, etc. Slow Growing Fast Growing Corals Algae Competition for Space

  • Structure
  • Protection
  • Food

St t Competition for Space

  • Protection
  • Food
  • Structure
  • Protection
slide-4
SLIDE 4

Corals and Algae in a Reef Without H bi Herbivores….

Fish, , Invertebrates, Turtles, etc. Slow Growing Fast Growing Corals Algae Competition for Space Competition for Space

Photos: Hughes et al 2007

slide-5
SLIDE 5
  • G. Davis
slide-6
SLIDE 6

Important Interactions Important Interactions

  • Corals and algae

g compete for space

  • Herbivores are

i l i i essential to maintain the equilibrium between algae and between algae and corals

  • Intact fish communities

are necessary for healthy reefs

slide-7
SLIDE 7

Human Activities Alter this Balance

Fish, Invertebrates,

Fishing Recreational Impacts

  • Turtles, etc.

p

  • +/

+/-

  • Corals

Algae

+

  • Climate

Change Pollution Lack of Public Awareness

slide-8
SLIDE 8

Climate Change Climate Change

  • What does this mean for Guam’s reefs?

What does this mean for Guam s reefs?

– Warmer waters  Increased coral bleaching, shifts in species distribution shifts in species distribution – Ocean acidification  May impact coral growth rates as well as other organisms that growth rates as well as other organisms that calcify, including invertebrates – Increased sea levels – ???

slide-9
SLIDE 9

Coral Bleaching on Guam Coral Bleaching on Guam

  • Two events over the last

5 years

– Corals and other

  • rganisms with

g zooxanthellae down to 5m were observed to bleach

  • Including fire corals, giant

l d clams, and anemones

  • In the 200x event we saw

mortality in recently bleached corals  rapidly p y covered in algae

  • In the 200x event we noticed

an increase in coral disease associated with the event associated with the event

slide-10
SLIDE 10

Ocean Acidification Ocean Acidification

  • Carbon Dioxide is absorbed by the ocean

Carbon Dioxide is absorbed by the ocean

  • As atmospheric CO2 increases, the

amount absorbed by the ocean increases amount absorbed by the ocean increases

slide-11
SLIDE 11

Fishing Fishing

  • Fishing has a direct effect on reef

Fishing has a direct effect on reef ecosystems

  • Fish are a renewable resource IF we
  • Fish are a renewable resource IF we

harvest them in a sustainable manner W d t id fi hi ti

  • We need to consider our fishing practices

in the context of these broader ecosystem th t threats

slide-12
SLIDE 12

Reef Resilience Reef Resilience

  • Preserve the Balance

Preserve the Balance

– Ensure that all parts of the ecosystem are in place place

  • Herbivorous fish and invertebrates
  • Apex predators

p p

  • Reduce Impacts

p

  • Pollution
  • Recreational Impacts

Guam Dept. of Agriculture

slide-13
SLIDE 13

How do we Balance? How do we Balance?

  • The role of Marine Protected Areas

The role of Marine Protected Areas

– Improved resilience – stabilizes coral cover

  • Enhance Herbivory

Enhance Herbivory

– Reduce take of herbivores in heavily impacted areas – this may be very important for reef y y p restoration

  • Enhance Reproductive Capacity in Stocks

– Choose to harvest fish after they’ve become reproductively mature

slide-14
SLIDE 14

DRAFT POSTER

Poster concept, design and art by Ellyn Tong

slide-15
SLIDE 15

Key Points Key Points

  • There are big threats to our reefs on the horizon

g

  • Herbivores are essential to maintain the

equilibrium between algae and corals

  • Apex predators play an important role in keeping
  • Apex predators play an important role in keeping
  • ur fish stocks healthy and robust
  • Fishers can help improve resiliency by making

p p y y g choices about their target fish

  • Enhance herbivory in restoration areas to help

restore the balance restore the balance

  • Increase reproduction by targeting fish above

the L50 and also leaving the really big fish

slide-16
SLIDE 16

Si Yu’os Ma’ase! Si Yu os Ma ase!

Questions?