thumb|upright=1.3|Aerial view of Barnum Island and [[Harbor Isle, New York|Harbor Isle from the west.]]
Barnum Island is a hamlet and census-designated place (CDP) in Nassau County, New York, United States. The population was 2,590 at the 2020 census. It occupies the eastern portion of an island situated between Long Island and Long Beach. That island, previously known in its entirety as Hog Island, consists entirely of the communities of Barnum Island and Island Park.
Barnum Island is an unincorporated area of the Town of Hempstead. Most of Barnum Island is separated from the Village of Island Park by the LIRR's Long Beach Branch rail line to Long Beach.
Barnum Island has its own fire district and school district, but is under contract with the Village of Island Park for fire and education services for its residents. Barnum Island is included in the Island Park School District and ZIP code (11558).
The E.F. Barrett Power Station is located within the hamlet.
History
Previously called Hog Island, after the feral pigs introduced by early European explorers to the Native Americans, it was later renamed for Sarah Ann Baldwin Barnum. It was also sometimes called Jekyl Island, after the name of the development company that bought it from the county.
Between 1851 and 1870, Sarah Ann's husband Peter owned large parcels of land on Long Island, though his primary business was a Manhattan clothier. Sarah Ann arranged the purchase of Hog Island for use as a "poor farm" – a self-supporting almshouse, a social innovation for that period, and the island was renamed in her honor.
Local lore connects the island's name to P.T. Barnum, the circus impresario, but this is incorrect, and likely due to confusion between "PT" and "PC" (Peter C.). Minimal development at that time included construction of several canals, before work was abandoned. One of those canals divides the Harbor Isle section from Island Park.
New developers bought the island in 1921, and started building about 10,000 properties built in the 700 acre Island Park section in the center of the island starting in 1922.
Geography
thumb|left|U.S. Census Map
According to the United States Census Bureau, the CDP has a total area of , of which is land and (28.24%) is water.
Demographics
Racial and ethnic composition
{| class="wikitable sortable" style="text-align:center;"
|+Barnum Island CDP, New York – Racial and ethnic composition<br><small></small>
!Race / Ethnicity <small>(NH = Non-Hispanic)</small>
!Pop 2000
!Pop 2010
!style="background-color: #ffffb3;" |Pop 2020
!% 2000
!% 2010
!style="background-color: #ffffb3;" |% 2020
|-
|White alone (NH)
|2,126
|1,914
|style='background: #ffffe6; |1,762
|85.48%
|79.29%
|style='background: #ffffe6; |68.03%
|-
|Black or African American alone (NH)
|8
|22
|style='background: #ffffe6; |69
|0.32%
|0.91%
|style='background: #ffffe6; |2.66%
|-
|Native American or Alaska Native alone (NH)
|0
|2
|style='background: #ffffe6; |4
|0.00%
|0.08%
|style='background: #ffffe6; |0.15%
|-
|Asian alone (NH)
|56
|64
|style='background: #ffffe6; |156
|2.25%
|2.65%
|style='background: #ffffe6; |6.02%
|-
|Native Hawaiian or Pacific Islander alone (NH)
|1
|0
|style='background: #ffffe6; |0
|0.04%
|0.00%
|style='background: #ffffe6; |0.00%
|-
|Other race alone (NH)
|7
|16
|style='background: #ffffe6; |34
|0.28%
|0.66%
|style='background: #ffffe6; |1.31%
|-
|Mixed race or Multiracial (NH)
|33
|19
|style='background: #ffffe6; |61
|1.33%
|0.79%
|style='background: #ffffe6; |2.36%
|-
|Hispanic or Latino (any race)
|256
|377
|style='background: #ffffe6; |504
|10.29%
|15.62%
|style='background: #ffffe6; |19.46%
|-
|Total
|2,487
|2,414
|style='background: #ffffe6; |2,590
|100.00%
|100.00%
|style='background: #ffffe6; |100.00%
|}
2020 census
As of the 2020 census, Barnum Island had a population of 2,590. The population density was . There were 1,062 housing units at an average density of .
The median age was 47.4 years. 14.8% of residents were under the age of 18 and 21.4% were 65 years of age or older. For every 100 females there were 96.8 males, and for every 100 females age 18 and over there were 96.7 males age 18 and over.
There were 1,026 households, of which 24.1% had children under the age of 18 living in them. Of all households, 48.9% were married-couple households, 19.6% were households with a male householder and no spouse or partner present, and 25.8% were households with a female householder and no spouse or partner present. About 26.1% of all households were made up of individuals and 10.0% had someone living alone who was 65 years of age or older.
Education
Barnum Island is in Island Park Union Free School District.<!--UNI 15480--> High school students go to Long Beach High School of the Long Beach City School District.
From circa 1968<!--2018 - 50 , source text: "After almost 50 years" --> to 2008, the Island Park district sent high school students only to West Hempstead High School, operated by the West Hempstead Union Free School District. From circa 2008 to 2018,<!--Source text: "It’s been nearly a decade since[...]"--> people living in the Island Park district could select between Long Beach and West Hempstead for high school education. In 2018 the Island Park school district stopped paying for Island Park residents to have the West Hempstead choice, and this was effective the 2019-2020 school year.