London has built something eco-friendly for the birds–the urban birds of the Bankside neighborhood, famous for the Tate Modern museum.  The architectural firm, 51% studios, has designed for the London Festival of Architecture, incorporating the theme of exchange–of knowledge, habitat, materials– three Nestworks, bird nesting boxes featuring a series of sophisticated ready mades: blocks, boughs and bushes.

The project, according to the architects, was informed by the ornithological work of Peter Holden, locally celebrated for setting up the annual peregrine falcon public views at the Tate Modern.

51% studios discovered that the standard hollow block used to build some of London’s most celebrated architecture is made from concrete with 55% recycled wood pulp, a material that when used in nestboxes, has proven to fledge more young birds.

Interior block dimensions are text book sizes for housing sparrows, which are radically in decline in the area. Nestworks are designed for other species as well, including blue tits, great tits, starlings, wrens, robins, and blackbirds.

Inspiration for the Nestworks comes from Witherford Watson Mann’s Bankside Urban Forest strategy, whose aim isn’t to literally to turn the area into a  forest, but to create green urban space, using trees, planted walls, and other ecological means. Unlike a traditional urban park, an urban forest is without distinct boundaries.

The London Festival of Architecture runs through July 4.