Coastal Wetlands: Important Ecosystems Facing Threats

1. 012 Wetlands

2. Wetlands Coastal wetlands are coastal watersheds that drain to the ocean or to an estuary or bay.

3. Coastal Oceans • Intertidal zones • Estuaries • Salt marshes • Seagrass beds • Muddy & sandy bottom communities • Mangroves • Coral Reefs

4. Ocean Productivity Open ocean <50 g C/m2/year Coral reefs 1000 g C/m2/year Mangroves 500 g C/m2/year Continental Shelf: Nonupwelling 200 g C/m2/year Coastal upwelling 300 g C/m2/year Seagrass beds 1000 g C/m2/year Estuaries and salt marshes 800 g C/m2/year Upwelling 300 g C/m2/year

5. Intertidal Zonation • The transition between terrestrial and marine environments • Zonation is a vertical banding of the organisms living on the rocky coastline. • The area between the highest high tide and lowest low tide. • These distinct bands occur in part from many complex physical and biological factors that effect marine organisms.

6. Which tidal cycle has the greatest effect on marine organisms living in the intertidal zone?

7. Tidal Zones on a Rocky Ocean Shore Splash Fringe Level High Tide Level Mid Tide Level Low Tide Level Low Fringe Level

8. Mostly shelled orgs Spray or Splash Zone High Tide Zone Middle Tide Zone Many soft bodied orgs and algae Low Tide Zone

9. Big Island

10. periwinkles ulva opihi Mussels & starfish

12. What are some stresses that affect the organisms residing in the intertidal zone?

13. Biotic factors affecting organisms living in the intertidal zone: • Competition for space and food • Predation • Reproduction • Substrate settlement preference • Osmoregulation

14. Abiotic factors affecting organisms living in the intertidal zone: • Salinity • Temperature • Air and light exposure • Tidal flow • Waves and current action • Substrate • Wind direction and strength • Dissolved O2 • Storms • Natural Disasters

15. What are some adaptations to living in the intertidal zone?

16. Estuaries are among the most productive marine ecosystems with high biomass of benthic algae, seagrass and phytoplankton

18. Wetlands in Hawaii • At one time contained an estimated 59,000 acres of wetlands • Over the last 200 years Hawaii has lost approximately 12 % of its original wetland acres. • The exact effect of the loss or degradation of Hawaii's wetlands on local fisheries is unclear. • It is estimated that only 1% of the Pacific island recreational and commercial species are estuarine-dependent. • Economically important estuarine fish: mullet, milkfish, shrimp, and the nehu, a tropical anchovy used as live bait in the pole-and-line skipjack tuna fishery.

19. Oahu Watershed

20. Traditional Hawaiian Uses of Wetlands

21. Seaweedslimu

22. Hooks andLures

23. Octopus Lure

24. Fishing Shrinesko‘a

25. Hawaiian Fish Pondsloko i‘a

26. Ahupua’a Ranges from the tip of the mtn to the reef area • Upland • Plains • Ocean

27. TheAhupua‘a

28. Salt Marsh

29. Salt Marsh

30. Salt marshes • Found from the Arctic to Southern Australia • Salt marshes grow in muds and sands that are sheltered by barrier islands. • Flood and ebb currents transport saltwater, nutrients, plankton and sediments in and out of the marsh.

31. Salt marshes • Vegetation zones due to tides and salinity • Wet grasses lands that grow along estuarine shores • Found from the Arctic to Southern Australia • Salt marshes grow in muds and sands that are sheltered by barrier islands. • Flood and ebb currents transport saltwater, nutrients, plankton and sediments in and out of the marsh. 600 species worldwide

32. Salt marshes Wetlands at the upstream side of Ka’elepulu Fish Pond, looking towards Kailua Bay

33. Salt marshes

35. He'eia Wetlands

36. Wetland Birds Black crowned night heron Sanderling Rudy Turnstone Hawaiian Coot Hawaiian Stilt Pacific Golden Plover Northern Pintail Duck Hawaiian Duck Wanderling tattler

37. Wetland Fish Mullet ‘O‘opu akupa Tilapia Milkfish

38. Wetland Inverts Anchialine ponds Opae ula

39. Wetland Plants aki'aki akulikuli mangrove bullrush

41. Waikiki & Diamond Head 1934

42. The value of coastal wetlands • Highly productive food factory • Serves as fish nurseries • Acts as a giant sponge: • The salt marsh absorbs large volumes of water, thus minimizing the impacts of flooding and erosion and recharging groundwater. • Filters polluted runoff from land • absorbing toxins and in some cases metabolizing them into harmless substances • Problem: • wetlands viewed as worthless land

43. Of the original 215 million acres of wetlands in the U.S. (excluding Alaska and Hawaii) , about 106 million acres remain. distribution of wetlands in the U.S. in the 1780s distribution of wetlands in the U.S. in the 1900s

44. Current distribution of wetlands and deepwater habitats

45. Major Causes of Wetlands Loss and Degradation Human Actions • Drainage • Dredging and stream channelization • Deposition of fill material • Diking and damming • Tilling for crop production • Levees • Logging • Mining • Construction • Runoff • Air and water pollutants • Changing nutrient levels • Releasing toxic chemicals • Introducing non-native species to the ecosystem • Grazing by domestic animals

46. Natural Threats • Erosion • Subsidence • Sea level rise • Droughts • Hurricanes and other storms

47. Estuaries • Estuaries are partially enclosed coastal bodies of water • Examples of estuaries include: • River mouths • Bays • Inlets • Gulfs • Sounds • Formed by a rise in sea level after the last Ice Age

48. Examples of estuaries Pu‘uloa

49. Classifying estuaries by water mixing • Vertically mixed • Slightly stratified • Highly stratified • Salt wedge

50. Sea Grasses 57 species worldwide