1. Science-based “rules of thumb” for the design of marine protected area networks
Mark H. Carr
Dept. of Ecology and Evolutionary Biology, University of California, Santa Cruz
Partnership for Interdisciplinary Studies of Coastal Oceans (PISCO)

2. Design Principles reflect MPA conservation goals
reflect fundamental ecological processes
reflect human dimensions
planning process that engages stakeholders
science guidance that is transparent, credible, responsive, understandable – “rules of thumb”
Science guidance needs to explain and becommunicated in ways that are understandable make sense

3. California MLPA: Conservation Goals
Protect natural diversity and ecosystem functions
Protect representative and unique habitats
Sustain and restore marine life populations
Ensure that MPAs are designed and managed as a network
NOTE: the lack of any reference to fisheries management or impacts!!

4. Design Criteria – MPA Network
Habitat (ecosystem) representation
Habitat (ecosystem) and MPA replication
MPA size
MPA spacing
Conservation level
What level of conservation or protection is afforded species and ecosystems based on the activities that might be allowed in an MPA?

5. Habitat and Ecosystem Representation
Identify ecosystems based on:
Bottom type and depth
Biogenic habitat (kelps, corals, sponges)
Oceanographic features
To identify those ecosystems, we use… and consider…
Estimate habitat distribution and abundance using GIS 5

6. Ecosystems vary by bottom type and depth

7. Ecosystems vary geographically
West Islands
North Mainland
Mid Islands
East Islands
South Mainland
Between and within biogeographic regions

8. Ecosystem Representation
“rules of thumb”
represent each ecosystem in MPAs across the network
include habitats across a range of depths
represent each ecosystem within and across biogeographic regions
In contrast to Jon’s terminology, habitats here are substrates (rock vs. sand) X key habitats 16 habitat types

9. Design Criteria – MPA Network
Habitat (ecosystem) representation
Habitat (ecosystem) and MPA replication
MPA size
MPA spacing
Conservation level

10. Ecosystem and MPA Replication
Why replicate ecosystems and MPAs in a network?
spread the risk of losing entire conservation tool to a local disturbance
enhances representation
replicate both the ecosystem and the type of MPA
critical to evaluation and adaptive management

11. Ecosystem and MPA Replication
What counts as an ecosystem replicate? 10 20 30 40 50 60 70 80
Square KM (or linear distance along coastline)
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
Estimated proportion of species
should be sufficient to encompass most of the species that live in the habitat
more area captures more species
should be sufficient to capture 90% of biodiversity

12. Ecosystem and MPA Replication
“rules of thumb”
replicate ecosystems and MPA types across the network
replicate within and across biogeographic regions
sufficient area of ecosystem to contribute to network
replicate each ecosystem in at least 3-5 MPAs within a region
In contrast to Jon’s terminology, habitats here are substrates (rock vs. sand) X key habitats 16 habitat types

13. Design Criteria – MPA Network
Habitat (ecosystem) representation
Habitat (ecosystem) and MPA replication
MPA size
MPA spacing
Conservation level

14. MPA Size
MPAs must be large enough so that adults remain within them throughout their lifetime
MPAs must be large enough to include multiple ecosystems to protect ecosystem connectivity
Achieving these goals are all about proper size and spacing among reserves. The two fundamental criteria are that…
This is not to imply that they need to be big and next to one another, rather as I’ll show you, there is a tradeoff between size and spacing.

15. Larger MPAs Protect More Species
More flatfish
Salmon
Some schooling fish
Few reef fish
100 – 1000 km
> 1000 km
Some schooling fish
Tunas
Many sharks
10 – 100 km
Some reef fish
Some flatfish
1 – 10 km
More reef fish
0 – 1 km
Many reef fish

16. MPA Size Guidelines “rules of thumb” Minimum area of 25 – 50 km2
Preferably 50 – 100 km2
Extend from the intertidal zone to deep waters, encompassing multiple ecosystems
25km2 = 9nm km2= 16nm2

17. Design Criteria – MPA Network
Habitat (ecosystem) representation
Habitat (ecosystem) and MPA replication
MPA size
MPA spacing
Conservation level

18. MPA Spacing
MPAs must be close enough together that young (larvae) can move from one protected ecosystem to another
MPAs contribute to replenishing one another and the fished populations in between them
Achieving these goals are all about proper size and spacing among reserves. The two fundamental criteria are that…
This is not to imply that they need to be big and next to one another, rather as I’ll show you, there is a tradeoff between size and spacing.

19. Populations Are Connected by Dispersal of Young
Populations contribute to replenishment of one another
Increase overall area replenished outside reserves per unit area within reserves
Although adults of many species have very limited home ranges, their young can move great distances. Most marine species produce young (called larvae) that are carried off by ocean currents, to end up replenishing populations somewhere else along the coast. Therefore, to assure that the young produced in a reserve replenish other reserves and the populations in between, reserves need to be spaced from one another in relations to how far these larvae travel.

20. Size and Spacing Guidelines
rules of thumb
Size
Spacing
Size:
km2
Spacing:
50 – 100 km apart
Tradeoffs in size and spacing
Number of Species
Here’s a graph that shows the number of algae, invertebrate and fish species whose young disperse the distance indicated along the bottom axis. Note that these distances are logarithmic scales increasing by an order of 10. Most of the seaweeds produce young that travel no more than a few kilometers. Invertebrates vary across the board, from meters to 100’s of kilometers, and larval fishes move the greatest distances from 10’s to 100’s of kilometers.
Algae and many species of invertebrates will replenish their populations within reserves on the order of 10 km. (SPACE) But the young of many species travel far beyond the size of a single reserve, suggesting that reserves should be spaced no more than 50 to 100 km apart from one another. (SPACE)
(SPACE) Note that size and spacing are inter-related. The smaller the reserve, the more and closer together they need to be. The larger the reserve, the farther apart they can be.
Data from Kinlan and Gaines 2003, Shanks et al 2003

21. MPA Spacing Guidelines
“rules of thumb”
maximum distance between protected ecosystems of 50 – 100 km
assessed separately for each ecosystem
can be constrained by distribution and availability of ecosystems
achieved most easily with multiple ecosystems in each MPA

22. Design Criteria – MPA Network
Habitat (ecosystem) representation
Habitat (ecosystem) and MPA replication
MPA size
MPA spacing
Conservation level

23. MPA Conservation Levels
if MPAs allow human activities, their conservation level may be diminished
predict ecosystem conservation level by comparing to no-take marine reserve
consider potential impacts to habitat, abundance of any species, community structure

24. MPA Conservation Levels
“rules of thumb”
only MPAs with high ecosystem conservation levels should count toward achievement of design guidelines

25. Conclusions - “rules of thumb”
based on MPA conservation goals and ecological processes
critical to transparent, credible, responsive, understandable science -based design of MPAs
facilitates engagement of stakeholders in planning processes

26. Thank You Science Advisory Team Stakeholder Groups
Design and application of support tools are a direct reflection of the planning process they were designed to facilitate, so it is necessary to quickly describe the MLPA planning process… using the MLPA goals, the science team was tasked with…
Create and present guidelines
Evaluate design proposals
Design and propose MPAs and networks

27. The Product:
MPAs established between 2007 and 2012 in four coastal regions
63 no-take reserves; 1291 km2, 9.4% of state waters
124 MPAs total covering 2197 km2, 16% of state waters
The central coast effort created a regional network of reserves and conservation areas (these CA’s allow some forms of fishing). 10 fully protected no-take marine reserves covering roughly 8% of the region for a total of 29 marine protected areas were created. And as I mentioned, the network in the section of coast is in its final stages of design as well. 27