Issues of Scale Both time & space – Time: waves, tides, day, year, ENSO – Space: local, regional, global Set how processes interact Scale invariance

Pacific Coastline 1 o latitude = 111 km

The Southern California Bight

The Santa Barbara Channel

Scale Invariance “ Details ” appear the same at all scales Makes understanding of marine processes difficult – always somewhere else to look Idea of “ fractal ” geometry

Time Scales Time scales of variability runs from minutes to decades Processes occur on particular scales Surface waves = minutes Wind forcing = days Climate = decadal

Time & Space Scales Time & space scales are linked by the processes driving them Large events correspond to long time scales – T = f(X) (& vice versa) – Mass analogy

Time & Space Scales Time & space scales are linked by the processes driving them Large events correspond to long time scales – T = f(X) (& vice versa) – Mass analogy

Detail & Time Scale The time scale over which processes are viewed influences the details observed Example – SST in CA Current

A Snapshot of CA Current April 1978 AVHRR - SST CZCS Chlorophyll Spatial variations on scales of 5-10 km SSTChl

Annual Mean SST

Spatial Detail & Time Scale The time scale of assessment influences the “ details ” observed Long time averages – large scales only Instantaneous – both small & large scales Time averaging removes small scale variations – “ the moving hand analogy ”

Scales for Marine Organisms Marine organisms have inherent time & space scales – Time: life duration, life cycle, etc. – Space: foraging, larval dispersion Different processes will interact with marine organisms based upon their scales

Life Cycles

Larger is longer… Larger have more (known) life stages

Larval Dispersion From Kinlan & Gaines [2003]

Dispersion & Time in Plankton From Siegel, Kinlan, Gaylord & Gaines [2003] Plankton Larval Duration (days) Genetic Dispersal Scale (km)

Scales for Marine Organisms The larger the organism the … longer its life span more life stages it has but no real effects on dispersal distance Larval dispersal is function of time “ in plankton ” Larger organisms forage & migrate under their own power & cover larger space scales These time scales will interact with physical & biological time scales of the system

So… can we use this??? Extended Kelp-Urchin-Otter Food Web – Add other factors Human harvest & regulation, climate, etc. – Assess time & space scales – Address management strategies

Otter-Kelp- Urchin Food Web Otters are the keystone predator of this food web Orcas

Otter-Kelp- Urchin Food Web Removing otters affects food web structure

Orcas HUMANS Add Human Harvest

Orcas HUMANS Other Marine Mammals Add Other Mammals

Orcas HUMANS Other Marine Mammals Add Climate Change Nutrient  ’ s due to climate Substrate  ’ s due to climate

Orcas HUMANS Other Marine Mammals Add Oil Spill Nutrient  ’ s due to climate Substrate  ’ s due to climate

What are the time & space scales for this system? Forcing of the base of food web is annual & over large space scales Many organisms are long-lived – but may be nearly fixed in space (otters, kelp forests, etc.) Climate is ENSO to PDO scales again over large spatial scales Oil spills will happen suddenly over variety of space and time scales

Orcas HUMANS Other Marine Mammals Nutrient  ’ s due to climate Substrate  ’ s due to climate BIOLOGICAL TIME

What are the time & space scales for this system? Anthropogenic factors follow “ legislative time ” – Both harvest policies & marine mammal protection – Transparency slows management policy changes How do fisheries adapt to changing scenarios? – How do fishermen learn? – Change in spatial & species targeting – Build up new markets…

How would you manage this system? What do you value? Fishery income vs. charismatic megafauna vs. recreational use vs. habitat biodiveristy vs. ??? Know the interrelationship among causal factors Follow the paths of food energy & information – Both are important

Flow Fish Settlement Habitat Recruitment Harvest Regulation Fishermen Market INFO Climate Flow, Fish & Fishing

How would you manage this system? Where are the critical juncture points? – Life history stage vs. keystone species vs. ??? Play out coupled scenarios – Most management today is single species – Not ready for quantitative multi-species management – Need assessment of the couplings (even loosely) Adapt to change – but anticipate its arrival!!

General Approach Focus on connections among components – Both food & information Know when & over which scale connections are robust Monitor the important causal links Adapt to a changing world

General Approach Focus on connections among components – Both food & information Know when & over which scale connections are robust Monitor the important causal links Adapt to a changing world