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HCC Water Quality Analysis

In this lab exercise you will be participating in an investigation of the quality of water in local rivers.

What types of pollutants may affect water of local rivers?There are many forms of pollution derived from human (and in some cases, natural) activities. Some types of pollutants that might affect water tested in this lab exercise are described below.

Some Factors Affecting Water Quality

Water Depth: shallow water allow sunlight penetration that favors the growth of phytoplankton, zooplankton, and limu.

Water Hardness: minerals are dissolved in the rain water after it touched the ground. Water that is “hard” contains calcium and magnesium compounds. If rainwater passes through soft rock, like chalk and limestone, it picks up these minerals. If it passes through hard rocks, such as granite or peaty soil, it does not pick up these minerals and so remains soft. General guidelines for classification of water; 0 to 60 mg/l of calcium carbonate is classified as soft; 61-120 mg/l as moderately hard; and 121 to 180 mg/l are hard; and more than 180 mg/l as very hard.

Salinity: the salinity (amount of salts dissolved in brackish or seawater) fluctuates with the tides, depths and proximity to freshwater streams and springs. Salinity may range from 2 to 32 ppt.

Circulation: water circulated with the incoming tide to wash sediments out to sea and prevent stagnation and accumulation of bottom sediments. Bottom sediments are composed of silt and layer of decaying detritus or muck. These decomposing sediments take dissolved oxygen out of the water and produced hydrogen sulfides. These sediments appear as black mud that smells like rotten eggs. In areas of the pond with this decomposing layer, Apple and Kikuchi (1975) report that a hydrogen sulfide level above 3 ppm is considered injurious to young fish.

Dissolved Oxygen: dissolved oxygen levels may range from 16 to 13 ppm. The mean sea level of 7.9 ppm indicated high levels of photosynthetic activity. Like temperature, the level of dissolved oxygen will vary throughout the day with light and cloud cover.

Turbidity (water clarity): the clarity of the water is related to the presence of mineral or organic particles suspended in the water. Clear water allows sunlight

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to penetrate and the cooler water at the bottom to warm up. Cloudy water as a result of high turbidity reduces this sunlight and may reduce the growth rate of the limu, phytoplankton and fish.

pH: There is great concern about the damaging effects of acid precipitation on aquatic and terrestrial ecosystems. Lakes, rivers and forests in the U.S., Canada, and Europe have suffered damage from rain, snow and fog. The acids arise from sulfur and nitrogen oxides in air emissions. Runoff from strip mines also can lead to acidification of waterways. Fish, invertebrates and microorganisms are all sensitive to the pH of the water in which they live. In Hawaii, our major source of acid comes from the emissions from the active volcano, Kilauea. It puts sulfur into the atmosphere and makes natural acid rain. There is also a small amount of natural hydrochloric acid (HCl) put into the atmosphere this way. Fortunately, our abundant rain and winds dilute the acid in the rain and mostly blow it out to sea, although a large desert area exists in one area of otherwise-lush Kilauea volcano due to acid fallout. The pH (degree of alkalinity or acidity) of the water is measures on a scale of 1 to 14, with 1 being the most acidic, and 14 being the most alkaline. Due to the presence of minerals in Hawaiian waters, the pH of brackish water is generally alkaline (8-9).

Water temperature: the temperature varies seasonally and throughout the day. In a healthy environment, the temperature is relatively even in the water column and ranges from 64oF to 88oF in Hawaii.

Nutrients: Nutrients like nitrate (NO3) and phosphate (PO4) are found in common plant fertilizers that help plants grow. Normally, these chemicals act as limiting factors in an aquatic ecosystem. The most common types of nutrient pollutants (eutrophiers) include untreated sewage and fertilizer run-off because both types contain a high nitrogen and phosphorous content. When present in excess, these nutrients cause an overgrowth of algae referred to as an “algal bloom.” These blooms can decrease the clearity and light penetration, which causes limu to die. As the limu decompose, dissolved oxygen is depleted. Decreased dissolved oxygen then adversely affects the fish population. If excessive nutrients increase the phytoplankton concentration to high levels, a potentially lethal situation occurs, especially during the night, especially when there is no sunlight and no wind, or circulation.. During the evening, the phytoplankton that were making oxygen during the day, stop as the photosynthetic “machinery” shuts down. Because the phytoplankton are also alive and need oxygen to live, they begin to take up the oxygen along with the other living organisms in the water. If there is a large amount of fish, there will be almost no oxygen left in the water. This causes the fish to come to the surface of the water to breath to breathe or gasp for air. Usually in Hawaii, the tradewinds and tidal circulation reduce the chance of this occurance.

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Chemical pollutantsAn environmental contaminant, or toxin, is a man-made chemical that hasthe ability to damage or injure organisms within an ecosystem. Environmental contaminants can come from a wide variety of sources (i.e. pesticides, sewage, herbicides, etc.) and can either directly kill an organism or move up the food chain through biomagnification.

Chemical pollutants typically can be placed into two categories: inorganic and organic pollutants. Inorganic pollutants include substances such as heavy metals (cadmium, lead, mercury, manganese) and salts (see above). Organic molecules are substances that contain carbon and hydrogen atoms, and there are many thousands of organic molecules produced through human industrial processes that can act as environmental toxins. Organic pollutants are the type of pollutantremoved by the water filters containing “activated carbon” (aka “activated charcoal”) that people commonly install in their kitchen sinks

Soil ErosionSoil erosion from human activities near the watershed may also have a negative impact on the ecosystem. Soil washing into the water decreases the water clarity, blocking sunlight that the limu needs to grow. When the bottom sediments of soil and decayed organism matter in the water get too thick, it may cause depletion of dissolved oxygen.

Invasive SpeciesOne of the most visible invasive plants is the introduced red mangrove (Rhizophora mangle). This small tree was introduced to Hawaii from seeds brought in from Florida in the early 1900s. Mangrove trees were introduced to the Islands to prevent soil erosion. The American Sugar Company planted seedlings on the upper slopes of Molokai. However, the mangrove quickly spread to the coastlines where it now thrives in brackish water on most of the Islands. The mangrove root system established itself within the walls of the fishpond. This causes the sediment tobe trapped, turning some fishponds into wetlands anf mudflats. Mangroves also block sunlight, preventing the growth of limu, on which ‘ama’ama (striped mullet) feed.

Invasive limu species are also spreading on the reefs and in fishponds, displacing native species and altering the species and altering these structures of the ecosystems. Two of the most common aggressive species are Gracilaria salicornia and Acanthophora specifiera.

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Gateway to Hawaii Reef Algae: http://www.botany.hawaii.edu/reefalgae/

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Sample TableWater Quality Data

Site A Site BTemperatureSalinity (refractometer)Dissolved OxygenTurbiditypH (pH meter)Water clarity (secchi disk)Nitrate (NO3)Plankton countWater hardnessTide ID plants

Formal lab report due next week as well as questions below

Water quality Questions1. How do tides affect water temperature?2. How does water temperature affect the solubility of dissolved gasses like

O2?3. What is water hardness?4. How is salinity related to water hardness?5. Why is dissolved oxygen less in saltwater than freshwater?6. When is dissolved O2 higher- day or night?7. What is the role of phytoplankton? How does phytoplankton affect the

level of dissolved O2?

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Assignment: LAB REPORT (due next lab)As part of a formal lab report, discuss each water sample in terms of its overall quality and potential risk to the environment. State in which samples pollutants were identified and what type of pollutants caused the quality to drop.

How to write a formal lab report:Step 1 - The Title Page: The title should be centered on the paper. The course name should be centered and written two spaces below the title. The date is centered two spaces below the course name. Your first name, followed by the name of your lab partners, should be in the lower right-hand corner. Typed papers with computer spell-checking make the best presentation. However, if that is not available, use black pen and make sure that your handwriting is neat. Proof read and correct minor spelling errors. Major errors may warrant recopying the page.

Step 2 - Purpose Statement: State the purpose of the lab or the hypothesis to be tested. Provide background information to assist the reader in following your objectives. Define any terms that a reader may be unsure of.

Step 3 - Materials and Procedure: The materials are listed separately. Use a short paragraph, written in third person past tense, to describe the methods used to determine the data. The paragraph should be general rather than step by step instructions.

Step 4 – Data Analysis: Present the data is some organized manner - a graph, map or table. Every entry must be clearly labeled. Graphs must be titled and axes labeled. All calculations and formulas should be presented in an organized format, with corrects units of measurements.

Step 5 - Results: Use separate paragraphs to summarize what the data for each sample is showing, identify causes and effects, use comparison and contrast, and evaluate what you have observed.

Step 6 - Discussion: The conclusion section discusses the results in the context of the entire experiment. Usually, the objectives mentioned in the "Introduction" are examined to determine whether the experiment succeeded. If the objectives were not met, you should analyze why the results were not as predicted. You need to address the following: What is the significance or meaning of the results? What were you suppose to discover from this activity? How could you apply what you have learned? Could this information be useful in predicting results for similar circumstances?

Include any possible sources of error, either in the procedure or in your techniques, especially if you did not obtain the expected results. Would your results be reproducible for others? Do not “fix” the data to meet your expectations. Finish with a summary statement - a final answer.

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Step 7- References: In this section you will list any literature that you have cited in the text. List ONLY those references that you have specifically cited. References are listed in alphabetical order, by the first letter of the first author's last name.

Sample Citations:For a JournalBrown, E.K., Cox, E.F, Tissot, B., Jokiel, P.L., Rodgers, K.S., Smith, W.R., & Coles, S.L.(2004). Development of benthic sampling methods for the Coral Reef Assessment and Monitoring Program (CRAMP) in Hawaii. Pacific Science, 7, 145-158.

For a BookThurman, H. & Trujillo, A. (2008). Essentials of Oceanography (9th ed.). NJ: Prentice Hall.

For an Online JournalAuthor, A. A., & Author, B. B. (Date of publication). Title of article. Title of Online Periodical, volume number(issue number if available). Retrieved from http://www.someaddress.com/full/url/

For a Sample Lab Report visit: http://csm.jmu.edu/biology/garrisne/physiology/SampleReport.htm.

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Fish Identification

kākū; great barracuda Indigenous(Sphyraena barracuda) Indo-Pacific and

Atlantic Eats: smaller fish Eaten by: humans, ulua Description: silvery, long, round in cross-section, with a pointed, protruding lower jaw, two dorsal fins spaced widely apart; has a large forked tail; often has small black blotches irregularly placed on the lower side; grows to almost 6 ft. Habitat: occurs alone or in small groups, often found in shallow water close to shore; gets into fishponds where it feeds on other fish Did you know? In Puna on the island of Hawaiʻi, the kākū is said to have bumped against canoes, usually at night when there were lights shining from the boats. Since olden times, mahiʻai (fishers) have had a special relationship with the kākū. The mahiʻai tamed certain large kākū called ʻōpelu mama by handfeeding them. Then they trained the tamed kākū to help catch ʻōpelu. The fisher summoned his kākū by pounding in rhythm on the bottom of the canoe. His fish would swim up from the deep and follow the canoe to a school of ʻōpelu. Then fishermen lowered a large circular net and fed the ʻōpelu with cooked, grated squash. The kākū would circle the school of fish and drive them into a tight ball and then the net would be raised full of fish. The fishermen would toss the ʻōpelu mama a fish as a reward. This way of fishing is still practiced on Maui.

 

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moi; threadifin Indigenous

(Polydactylus sexfilis) Indo-Pacific

 Eats: small fish, shrimp, crabs

 Eaten by: humans, kākū ulua

 Description: silver in color; has six threadlike rays on the pectoral fins; a bulbous snout; underslung mouth; distinctive sweptback fins and a deeply forked tail; grows to about 12 in. Adults are called moi; juveniles are called moi liʻi.

 Habitat: Adult moi are commonly found along rugged coastal shorelines with strong wave action; juveniles are found over calmer, nearshore areas with sandy bottoms; does not swim at the surface.

 Did you know? In olden days, large schools of moi were said to foretell disaster of chiefs. Moi are delicious to eat; they were highly prized by the aliʻi (chiefs) and kapu to commoners. Schools of young moi (moi liʻi) can be spotted close to shore from mid-August through October. ʻEhu moi refers to foam of sea where moi are found. Fishers call this fish the wily moi because it is difficult to catch.

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āholehole; Hawaiian flagtail Endemic

(Kuhlia sandvicensis)

 Eats: small fish, small crabs and shrimp, insect larvae

 Eaten by: humans, larger carnivorous fish, ulua, kākū, eels

 Description: bright silvery with bluish color on back, but changes color to match habitat; large scales and large eyes; 6-10 in. long

Habitat: juveniles in lower reaches of streams; adults in brackish water, tidal pools, and holes along the outer edges of the reef

 Did you know? Āholehole means “sparkling” in Hawaiian. In the adult stage, it is called āhole. Hawaiians placed āholehole under house posts on the east side to keep away a kahuna who might predict trouble for the family. Hawaiians also placed offerings of a white ʻamaʻama or āholehole along with a red weke or kumu under the entrance of a new hale (home) to strip evil away. “Hole” in āhole means “to strip away.” According to one story, a chiefess in Hilo yearned for āholehole from Waiʻakolea in distant Puna. A runner delivered the fish to her wrapped in limu kala from the fishpond, and the fish was still breathing!

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ulua aukea; pāpio; giant trevally Indigenous

(Caranx ignobilis) Indo-Pacific

Eats: smaller fish, and forages on the bottom for crustaceans and other invertebrates

Eaten by: humans

Description: silvery on the sides and undersides and bluish or greenish on the back with deeply forked tails. The narrow place at the base of the tail is reinforced by specially strengthened scales called scutes; grows to over 5 ft. with a weight of up to 200 pounds.

Habitat: schools of ulua frequently patrol reefs; young fish (less than 4 in.) swim in protected bays and ponds.

Did you know? There is a Hawaiian proverb spoken in admiration of a warrior who does not give up without a struggle. ʻAʻohe ia e loaʻa aku, he ulua kāpapa no ka moana. (He cannot be caught for he is an ulua fish of the deep ocean.) The ulua's color pattern, like that of many marine animals, is dark on top and light below. This counter-shading camouflages it in open water. In the Hawaiian name, ulua aukea, “kea” means white. In old Hawai'i, this prized fish could be substituted for a human in a ceremony calling for a human sacrifice. This may have been because the word ulua refers to “man” or “sweetheart” in love songs. Hawaiian women were forbidden to eat ulua.

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pualu; yellowfin surgeonfish Indigenous(Acanthurus xanthopterus) East Africa to the

AmericasEats: phytoplankton and zooplankton (when young), limu growing on sandy bottoms

Eaten by: larger carnivorous fish

Description: oval, compressed (thin) body; purplish gray with yellow and blue banded dorsal (back) and anal fins; has a black caudal (tail) spine and two knifelike spines or scalpels at the base of the tail; grows to 22 in.

Habitat: shallow waters with sandy bottoms

Did you know? The yellow pectoral fins are important for identification of the pualu since it can alter its body color to almost black with a white ring around the tail. The pualu uses the two knifelike spines at the base of its tail to defend itself and to help capture prey.

 

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ʻoʻopu naniha; goby Endemic

(Stenogobius hawaiiensis)

Eats: limu, worms, shrimp, small crabs, zooplankton, insect larvae

 Eaten by: humans, ulua, moi, kākū, pūhi

 Description: yellow-brown with black stripe extending down below eyes; 4 - 5 in long; both sexes display black bars on bodies and red border on edge of dorsal fins during courtship; has suction disc, but does not climb beyond lower reaches of streams.

 Habitat: stream bottom in lower reaches of streams

 Did you know? This ʻoʻopu feeds by thrusting its snout into the sediments of the stream bottom. If you see a stream bottom with many tiny craters, this is a clue that naniha has been feeding there. In olden times, fishers gave offerings to the ʻoʻopu fish god named Holu. If they did not provide offerings, such as a black pig, a white chicken, root of the black awa, dark coconut, or red fish, it was believed that the ʻoʻopu would not be fat or plentiful.

 

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ʻamaʻama; striped mullet Indigenous

(Mugil cephalus) Pacific

 Eats: phytoplankton, diatoms and detritus; feeds primarily off the bottom, taking in sand and filtering out the organic material through its gills

 Eaten by: humans, kākū, moi, ulua

 Description: silvery or gray with long body that is round or oval in cross section; has characteristic blue spot at the base of the pectoral fin; has blunt snout, a flattened head and large scales and two widely separated dorsal fins; lacks teeth of any distinction; can grow to 18 in.

 Habitat: shallow, often brackish coastal waters, easily raised in fishponds

 Did you know? Mature ʻamaʻama are called ʻanae. ʻAnae go to the open ocean to spawn from December - February. Waiʻanae is literally “mullet water.” Hawaiians referred to ʻamaʻama as “puaʻa kai” (sea pig) and used them when a pig was not available for ritual offerings.

 

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pūhi-lau-milo; undulated moray eel (Gymnothorax undulates)

IndigenousEast Africa to the

Americas

Eats: smaller fish, shrimp, crabs

Eaten by: ulua

Description: 3 - 5 ft. long muscular body has tough slippery, skin without scales; has narrow jaws full of long sharp teeth, including a row down the center of the mouth; top of head is sometimes greenish-yellow; body color varies from dark brown with light speckles and irregular vertical net-like markings to the reverse, almost white with irregular brown blotches; larvae are long, clear and ribbonlike.

Habitat: lives in crevices and holes, and in spaces between the rocks in walled-fishponds

Did you know?You should not attempt to play with or feed this pūhi; it can hurt you! It has a strong sense of smell and is more active at night. This predator can also survive on only one meal for a long time.The Hawaiian name means leaf of the milo tree. Why do you think it has that name? Hawaiians caught this pūhi using nets, spears and hooks. It is an ʻaumakua (personal god) for some families.

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Invertebrate Identification

kūhonu; white crab; haole crab; Indigenousblood-spotted swimming crab Indo-Pacific(Portunus sanguinolentus)  

Eats: dead or dying fish, small shrimp, worms

Eaten by: pūhi, kākū, ulua, moi

 Description: has strong sideways-pointing spine on each side of the carapace, which is the hard shield covering part of the body; carapace is marked with three red spots; can attain up to 7 in. across the carapace and an ‘arm-spread’ of 18 in. Habitat: sandy, muddy areas from the shorelines to depths of 100 ft. This species is protected by law and can only be gathered if the carapace is at least 4 in. wide. Did you know? The Hawaiian name of this crab, kūhonu, means “turtle back. ” 

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aloalo; white mantis shrimp Indigenous

(Oratosquilla calumnia) Indo-Pacific Eats: soft-bodied worms, shrimp, small fish, crabs, snails Eaten by: humans, puffer fish, ulua, moray eelsDescription: dangerous bottom-dwellers; light transparent gray, tan, or reddish brown with dark marks on the appendages on either side of the tail; has eight pairs of legs, the last three are used for walking; grows to 6 - 8 in. Habitat: lives in muddy, sometimes brackish water areas in U-shape burrows Did you know? You should not attempt to catch this shrimp with bare hands! They are aggressive carnivores that smash or spear their prey. Their pincers are folded up under their body and when they use them to strike prey, it's one of the fastest movements known in the animal kingdom!

 

 

 

 

 

 

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moʻala; long-eyed swimming crab Indigenous

(Podophthalmus vigil) Indo-Pacific

Eats: dead or dying fish, small shrimp, worms

Eaten by: pūhi, kākū, ulua, moi

Description: the eyestalks of this crab are amazingly long and can either be held direct or folded back into grooves along the front of the carapace. Individuals are brown to pinkish in color; grows to about 5 in. (carapace width).

Habitat: lives on soft muddy bottoms and can tolerate brackishwater conditions

Did you know? The Latin species name of this crab means “watchful.” These crabs are seldom seen by divers and snorkelers because of their habitat.

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ʻopaeʻoehaʻa; freshwater prawn Endemic

(Macrobrachium grandimanus)

Eats: detritus; small pieces of plant and animal matter

Eaten by: humans, moi, pāpio

Description: light to dark brown; one pincer is larger than the other; has distinctive striped pattern; 3 in. long

Habitat: lower reaches of streams and estuaries

Did you know? The Hawaiian name ʻoehaʻa means “to walk crookedly” which describes the uneven gait of this native prawn as it walks with its one large and one small claw. The female ʻōpae carries her eggs attached to modified swimmerets under her tail. When the eggs hatch about 3 to 4 weeks later, the tiny larvae go downstream, out to sea. They develop further in the ocean and then make their way back up to a stream where they spend their adult lives.

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papaʻi; blue pincher crab Indigenous

(Thalamita crenata) Indo-Pacific

Eats: limu, mangrove detritus; small pieces of plant and animal matter, snails; eats more in quantity and more animal matter at spring tide, low tide, and during daytime

Eaten by: humans, pāpio, pūhi, moi

Description: gray-to greenish-brown, sometimes pink body; white-tipped claws have a broad black band; upper segment of pincers are blue; grows to a carapace width of 5 in.

Habitat: sandy, muddy areas in brackish and salt water

Did you know? Unlike most swimming crabs, the blue pincher crab forages for prey more actively during the daytime. Scientists have found that, just like people, the blue pincher crabs may use landmarks to find their way home. When these crabs are removed from their home hole, they rely on their memory and knowledge of the space around them to find their way home! These crabs also have a more flexible way of orienting themselves than other crabs.

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Birds

ʻaukuʻu; black-crowned night heron Indigenous(Nycticorax nycticorax hoactli Americas, Africa, Eurasia and

the Pacific

Eats: small fish, shrimp, larvae of aquatic insects, and young chicks of other water birds

Eaten by: when young, injured or sick, this bird might be eaten by dogs, cats and mongoose

Description: has a glossy greenish black coloring on its back, feathers and on the top of the head; the under parts are white; neck, wings, and legs are all long; looks hunched over with its head usually tucked down to its shoulders. Adults are 23 - 26 in. tall with a wingspan of 43 - 45 in. wide.

Habitat: marshes, ponds, streams, lagoons, swamps, exposed reefs, and tide pools; also frequents aquaculture sites. It lives on all the main islands except Lānaʻi. The call of the night heron is a hoarse “quok.”

Did you know? Hawaiians call someone who spies on others, “Aukuʻu kiaʻi loko” (Heron who watches the [fish in the] pond). The ʻaukuʻu are very intelligent birds with very sharp eyesight, which allows them to escape from predators. They are nocturnal as indicated by the name night heron. At aquaculture sites, they know when it's pauhana. They can be seen flying onto pond fields and shrimp farms when the workers drive away.

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ʻAlae keʻokeʻo; Hawaiian coot Endemic

(Fulica Americana alai) Endangered

Eats: submerged aquatic plants, limu alolo, small fish and insects

Eaten by: dogs and cats; mongooses and ʻaukuʻu; (chicks are also eaten by rats)

Description: black bird with white rump and white frontal shield; dark legs with lobed toes; pointed, chicken-like light colored bill

Habitat: saltwater and freshwater ponds and open marshes where it can dive for food

 Did you know? These endangered waterbirds build their nests among the grasses around a pond where predators can attack! Be sure to keep your dogs on a leash if you walk near a pond where birds could be nesting. According to Hawaiian legend, the sacred ʻalae are children to the goddess Hina.