Comprehensive evaluation of marine mammals in coastal ecosystems by Claudio Iturra
Species: Gray whale, Humpback whale, Blue whale, Minke whale
Habitat: Migrate through coastal waters, feed in upwelling zones
Detection: Large acoustic signatures, surface behavior
Key Factors: Krill abundance, water temperature 8-15°C
Species: Orcas, Pilot whales, Sperm whales
Habitat: Deep coastal waters, continental shelf edge
Detection: Echolocation clicks, social calls
Key Factors: Fish/squid abundance, depth >200m
Species: Bottlenose dolphin, Harbor porpoise, Pacific white-sided dolphin
Habitat: Nearshore waters, bays, estuaries
Detection: High-frequency echolocation, group behavior
Key Factors: Small fish schools, salinity 32-35 ppt
Species: Harbor seals, Sea lions, Elephant seals
Habitat: Rocky shores, beaches, kelp forests
Detection: Haul-out sites, diving patterns
Key Factors: Breeding sites, fish availability
Species: Southern sea otter
Habitat: Kelp forests, shallow coastal waters
Detection: Surface feeding, tool use behavior
Key Factors: Kelp coverage, urchin/shellfish density
Species: Vaquita, North Atlantic right whale, Manatees
Habitat: Specific coastal regions, warm waters
Detection: Specialized monitoring, satellite tracking
Key Factors: Critical habitat protection, low vessel traffic
Hydrophones detect vocalizations, echolocation clicks, and breathing sounds
Range: 1-50 km depending on species
Frequency: 10 Hz - 150 kHz
GPS/Argos tags track movement patterns and diving behavior
Accuracy: ±150m - 1km
Duration: Weeks to years
Ship-based, aerial, and shore-based observations
Range: 0-10 km visibility dependent
Conditions: Beaufort scale ≤3
Water sampling to detect genetic material
Detection: Species presence/absence
Sensitivity: ng/L concentrations
Automated monitoring of haul-out sites and surface behavior
Coverage: 24/7 monitoring
Resolution: Individual identification
Satellite imagery for habitat assessment and large whale detection
Resolution: 0.3-30m pixels
Coverage: Global, daily revisit
Surface: 8-25°C optimal range
Thermocline: Depth varies 20-200m
Impact: Affects prey distribution and metabolism
Measurement: CTD, satellite SST, autonomous gliders
Range: 32-36 ppt in coastal waters
Halocline: Sharp gradients near river mouths
Impact: Affects buoyancy and osmoregulation
Sources: River discharge, precipitation, evaporation
Upwelling Winds: Parallel to coast, 5-15 m/s
Seasonal: Spring/summer upwelling favorable
Impact: Drives nutrient transport and primary productivity
Measurement: Buoys, satellites, weather stations
Upwelling Index: m³/s per 100m coastline
Indicators: Cold SST, high chlorophyll
Impact: Brings nutrients to surface, supports food web
Hotspots: California, Peru, Benguela currents
Currents: 0.1-2.0 m/s surface velocity
Eddies: 10-200 km diameter
Impact: Transport prey, affect migration routes
Measurement: ADCP, drifters, altimetry
Nitrate: 0-45 μmol/L
Phosphate: 0-3 μmol/L
Silicate: 0-150 μmol/L
Impact: Limits primary productivity and food availability
Krill: 0.1-100 g/m³ biomass
Fish Schools: Anchovy, sardine, herring
Zooplankton: Copepods, euphausiids
Measurement: Acoustic surveys, net sampling
River Discharge: 10-10,000 m³/s
Seasonal Variation: Spring snowmelt peaks
Impact: Creates estuarine gradients, affects salinity
Nutrients: Terrestrial input, agricultural runoff
Where: τ = wind stress, ρ = air density, f = Coriolis parameter, ρw = water density, L = coastline length
Offshore transport per unit width due to wind stress
Where: Pmax = maximum photosynthesis rate, I = irradiance, Ik = saturation parameter
Combines prey abundance with foraging efficiency
Where: Wi = weight for parameter i, Si = suitability score for parameter i
Probability of detecting animals given survey effort and availability
Where: SL = source level, TL = transmission loss, NL = noise level, DI = directivity index
Where: a = normalization constant, M = body mass, b = scaling exponent (~0.75), T = temperature