Cockrell Butterfly Center (Houston Museum of Natural Science)

Founded in 1909, the Houston Museum of Natural Science moved into its present building in Hermann Park, completed in 1969. In the early 1990s the museum added a wing devoted to insects: the Cockrell Butterfly Center and the Brown Hall of Entomology opened together in 1994, the butterfly centre on schedule in July. The design was entrusted to the Houston firm Hoover Architects, then part of the 3D/I group. According to the American Institute of Steel Construction's journal, the project was delivered for $5,847,710, more than 6 percent under its original budget.

The centre had a first renovation in 2007. In September 2022 it closed again for a more extensive campaign: the contractor Lakeview Glass and Mirror replaced all 535 panes of glass, while the paths were widened and resurfaced, the lighting renewed and benches added for accessibility. The centre reopened in spring 2023. The adjoining Brown Hall of Entomology is due to close on 10 August 2026 for its own renovation, with reopening announced for 2027.

The exhibit space is a truncated glass cone about 75 feet (23 m) high, topped by a sloping glazed roof. The frame is built mainly of round steel tubes: wall trusses connect to the roof truss system, a curved hollow-section compression ring closes the roof, and slender tie rods arranged as X-bracing around the whole circumference keep the structure stable.

The chief challenge was to withstand the Category 5 hurricane winds of the Gulf Coast without shading the interior or obstructing the butterflies' flight. A track on the roof lets a cleaning platform travel around the cone. The panes installed in 2022-2023 are insulating units of tempered and laminated glass. Inside, the temperature is kept between 75 and 80 °F with 70 to 80 percent humidity; the large central tree, the only artificial element of the setting, conceals the air circulation system.

The conservatory recreates a tropical rainforest over three levels, enlivened by a 50-foot waterfall. More than 1,500 butterflies live there at any one time. They arrive by mail as chrysalids, up to 1,000 a week, from butterfly farms in Central and South America, Southeast Asia and Africa. Their average lifespan is about two weeks, ranging from a few days for the Atlas moth to a couple of months for some long-winged species.

Labelled plants include a coffee tree, a chocolate tree, pride of Trinidad, the national tree of Trinidad, which flowers year-round, pineapple plants, a miracle berry bush and a range of orchids. Emergence chambers display thousands of chrysalids in which butterflies can be seen hatching, and a green iguana lives in an enclosure within the forest.

The centre is on Level 1 of the Houston Museum of Natural Science, on the northern edge of Hermann Park, and is ticketed separately from the main museum. The same complex combines the rainforest, an insect zoo and an entomology hall with live and preserved arthropods. Allow about an hour, more to linger at the emergence chambers. Through the daily Flight School programme, offered on a first-come basis, visitors can release a newly emerged butterfly into the forest themselves. The visit pairs well with the museum's palaeontology and mineral halls and with the nearby McGovern Centennial Gardens in Hermann Park.