As of the census[5] of 2000, there were 1,645 people, 639 households, and 423 families residing in the CDP. The population density was 218.1 inhabitants per square mile (84.2/km2). There were 692 housing units at an average density of 91.7 per square mile (35.4/km2). The racial makeup of the CDP was 24.74% White, 0.73% African American, 0.67% Native American, 36.84% Asian, 7.23% Pacific Islander, 2.07% from other races, and 27.72% from two or more races. Hispanic or Latino of any race were 9.18% of the population.
There were 639 households, out of which 25.5% had children under the age of 18 living with them, 49.0% were married couples living together, 12.2% had a female householder with no husband present, and 33.8% were non-families. 26.9% of all households were made up of individuals, and 9.2% had someone living alone who was 65 years of age or older. The average household size was 2.57 and the average family size was 3.10.
In the CDP the population was spread out, with 22.1% under the age of 18, 7.7% from 18 to 24, 25.3% from 25 to 44, 27.5% from 45 to 64, and 17.3% who were 65 years of age or older. The median age was 42 years. For every 100 females, there were 91.5 males. For every 100 females age 18 and over, there were 89.2 males.
The median income for a household in the CDP was $38,026, and the median income for a family was $45,192. Males had a median income of $29,333 versus $25,000 for females. The per capita income for the CDP was $21,495. About 9.2% of families and 13.7% of the population were below the poverty line, including 17.1% of those under age 18 and 6.3% of those age 65 or over.
Two schools, Konawaena Middle School and Konawaena High School,[8][9] are on a campus partially in Captain Cook CDP and partially in Kealakekua CDP.[6][10][11]
Henry Ōpūkaha`ia (1792–1818), a resident of Kealakekua, at 15 years old Ōpūkaha`ia boarded the Triumph to New Haven, Connecticut, where he was educated at Yale and was the impetus for Christian missionaries' arrival in Hawaii in 1820
Ellison Shoji Onizuka (1946–1986), American astronaut lost in the destruction of Space Shuttle Challenger
Douglas A. Zembiec (1973–2007), U.S. Marine Corps officer, Iraq and Afghanistan veteran, Silver Star, Bronze Star and two-time Purple Heart recipient
^"KONAWAENA MIDDLE SCHOOL CAMPUS MAP"(PDF). Konawaena Middle School. Retrieved October 11, 2020. - Shows that the middle and high school share the same plot.
