Native Hawaiian Streams & Native Hawaiian Streams & BioassessmentBioassessment

• Importance of streams to the Importance of streams to the HawaiiansHawaiians

• Native stream creaturesNative stream creatures

• Bioassessment of Hawaiian StreamBioassessment of Hawaiian Stream

The Importance of WaterThe Importance of Water

• Ancient Hawaiians placed a supreme value Ancient Hawaiians placed a supreme value on water itself. on water itself.

• The Hawaiian word for water is The Hawaiian word for water is waiwai, , • WaiwaiWaiwai is the word for wealth or value. is the word for wealth or value. • KumuwaiKumuwai means both the source of wealth means both the source of wealth

as well as the source of a stream. as well as the source of a stream. • The translation of our concept of the The translation of our concept of the

watershed into Hawaiian is watershed into Hawaiian is aina kumu waiaina kumu wai or the land that is the source of the water. or the land that is the source of the water.

• Without clean and ample free flowing Without clean and ample free flowing streams native plants and animals could not streams native plants and animals could not have survived. have survived.

• Without these plants and animals, native Without these plants and animals, native Hawaiians could not prosper and be Hawaiians could not prosper and be wealthy. wealthy.

Waikaumalo Stream, Hawai'iWaikaumalo Stream, Hawai'i

Life in Hawaiian StreamsLife in Hawaiian Streams

Animals Native to HawaiiAnimals Native to Hawaii

• 5 native species of 5 native species of fishes (four endemic, fishes (four endemic, one indigenous, i.e., one indigenous, i.e., native but found native but found elsewhere too)elsewhere too)

• 2 species of crustacean 2 species of crustacean (all endemic) (all endemic)

• 3 species of mollusk (all 3 species of mollusk (all endemic). endemic).

Hawaii's Native Stream AnimalsHawaii's Native Stream Animals

‘ ‘O'opu alamo'oO'opu alamo'o

'O'opu nopili'O'opu nopili

'O'opu nakea'O'opu nakea

'O'opu naniha'O'opu naniha

'O'opu akupa'O'opu akupa

‘‘O ‘opu spacing in StreamO ‘opu spacing in Stream

Hawaii's Native Stream AnimalsHawaii's Native Stream Animals

‘ ‘Opae kuahiwiOpae kuahiwi Opae 'oeha'aOpae 'oeha'a

Hawaii's Native Stream AnimalsHawaii's Native Stream Animals

HihiwaiHihiwai

HapawaiHapawai

Pipiwai Pipiwai

Geographic IsolationGeographic Isolation

• The Hawaiian Archipelago, The Hawaiian Archipelago, situated in the middle of the situated in the middle of the Pacific Ocean.Pacific Ocean.

• It is the most isolated landmass in It is the most isolated landmass in the world.the world.

• The west coast of the U.S. is The west coast of the U.S. is 2,400 miles away and Japan is 2,400 miles away and Japan is 3,800 miles away3,800 miles away

• Hawaiian freshwater animals Hawaiian freshwater animals evolved from marine forms.evolved from marine forms.

• Isolation has resulted inIsolation has resulted in a sparse a sparse freshwater fish populationfreshwater fish population

Characteristics of Hawaiian StreamsCharacteristics of Hawaiian Streams

1.1. They are small compared to larger They are small compared to larger streams in the US mainland. streams in the US mainland.

2.2. Numerous waterfalls. This feature gives Numerous waterfalls. This feature gives the stream a steep profile.the stream a steep profile.

3.3. Stream flow tracks rainfall pattern. Stream flow tracks rainfall pattern. FreshetsFreshets: short-duration, high-volume flows due : short-duration, high-volume flows due

to heavy rainfallto heavy rainfall

Life in Hawaiian streams have adapted to Life in Hawaiian streams have adapted to life in these highly energetic, sometimes life in these highly energetic, sometimes violent, and ever changing violent, and ever changing environment .environment . • Wailua Valley, Kaua'iWailua Valley, Kaua'i

Importance of FreshetsImportance of Freshets

• Flash floods flush away rotting Flash floods flush away rotting organic debris.organic debris.

• They remove fine sediments that They remove fine sediments that can smother the eggs of stream can smother the eggs of stream animals. animals.

• They open up the stream where it They open up the stream where it flows into the seaflows into the sea

• Flood waters entering the sea Flood waters entering the sea provide a biological signal.provide a biological signal.

Adaptations to Hawaiian StreamsAdaptations to Hawaiian Streams

• AdaptationsAdaptations: structures or features unique to a : structures or features unique to a species, or a group of species, which allow species, or a group of species, which allow them to survive and reproduce in a specific them to survive and reproduce in a specific habitat . habitat . – Random mutation in the genetic code (DNA) of Random mutation in the genetic code (DNA) of

an animal.an animal.

– Natural selection through the environment of a Natural selection through the environment of a species. species.

The Mauka (mountain) to Makai (sea) The Mauka (mountain) to Makai (sea) ConnectionConnection

• Hawaiian freshwater animals Hawaiian freshwater animals evolved from marine forms. evolved from marine forms.

• These animals still maintain a These animals still maintain a strong dependence upon the sea.strong dependence upon the sea.

• AmphidromyAmphidromy: the adults live and : the adults live and breed in fresh water streams, breed in fresh water streams, while the newly hatched larvae while the newly hatched larvae swim out to sea and remain there swim out to sea and remain there for several months before for several months before returning to freshwater.returning to freshwater.

• Hakalau Stream, Hawai'i Hakalau Stream, Hawai'i

Amphidromous Life CycleAmphidromous Life Cycle

• What might be an advantage to this type of life cycle?What might be an advantage to this type of life cycle?– The larvae in the ocean provide a reservoir for each species to The larvae in the ocean provide a reservoir for each species to

repopulate streams after catastrophic events such as hurricanes, repopulate streams after catastrophic events such as hurricanes, flashfloods, and lava flows flashfloods, and lava flows

– In addition, larvae are also moved by ocean currents to other streams In addition, larvae are also moved by ocean currents to other streams and even islands, which ensures dispersal and maintains a complete and even islands, which ensures dispersal and maintains a complete gene pool. gene pool.

Climbing WaterfallsClimbing Waterfalls

• Some species of fish have Some species of fish have adapted their pelvic sucking adapted their pelvic sucking disk to climb waterfalls.disk to climb waterfalls.

• The pelvic sucking disk also The pelvic sucking disk also helps in maintaining position. helps in maintaining position.

• The ‘o‘opu nopili’s mouth has The ‘o‘opu nopili’s mouth has evolved to also act like a evolved to also act like a suction cup which aids in suction cup which aids in climbingclimbing

Threats to Native SpeciesThreats to Native Species

• Hawaii's stream environments are poorly Hawaii's stream environments are poorly surveyed surveyed

• Huge die-offs of native ‘Huge die-offs of native ‘o‘opuo‘opu chronically chronically occur in de-watered streams which are occur in de-watered streams which are preceded by rampant disease in the population.preceded by rampant disease in the population.

• What factors contribute to these die-offs?What factors contribute to these die-offs?

Diversion of WaterDiversion of Water• Development has diverted water Development has diverted water

from streams for potable water, from streams for potable water, agriculture and hydropower.agriculture and hydropower.

• Diverted water…Diverted water…– Creates physical barriers between Creates physical barriers between

streams and the open ocean.streams and the open ocean.– Reduce available habitat and distorts Reduce available habitat and distorts

the natural rhythm of water the natural rhythm of water movementmovement

– Reduce flow which erodes the food Reduce flow which erodes the food base which supports native stream base which supports native stream species in favor of less-preferred species in favor of less-preferred slow-water tolerant forms and other slow-water tolerant forms and other invasive species .invasive species .

Alien and Invasive SpeciesAlien and Invasive Species

• Today more than 50 species Today more than 50 species of alien fishes, of alien fishes, invertebrates, reptiles, invertebrates, reptiles, amphibians and plants are amphibians and plants are established in our streams established in our streams and reservoirs and reservoirs

• Many of these species were Many of these species were intentionally released intentionally released

• Others were simply dumped Others were simply dumped in our streams with no in our streams with no thought given to possible thought given to possible consequences.consequences.

Invasive SpeciesInvasive Species

• Invasive species increase Invasive species increase predation and competition on predation and competition on native species with few native species with few natural defenses.natural defenses.

• It is suggested that invasive It is suggested that invasive species are transmitting species are transmitting parasites to native stream parasites to native stream fishes.fishes.

• How do we assess the health How do we assess the health of our streams?of our streams?

What can you do?What can you do?

• Maintain the mauka-Maintain the mauka-makai lifeline to ensure makai lifeline to ensure healthy populations of healthy populations of stream flora and faunastream flora and fauna

• Riparian (streamside) Riparian (streamside) vegetation is neededvegetation is needed

• Prevent the release of Prevent the release of additional alien species additional alien species into the streaminto the stream

• Keep the streams cleanKeep the streams clean• Minimize pollutionMinimize pollution

• LEARN MORE!LEARN MORE!