In a gem of a piece, photographer Roberto (Bear) Guerra chronicles the species loss the LA River has suffered since being encased in concrete with photographs of specimens from the Western Foundation for Vertebrate Zoology and the LA County Natural History Museum.
An important photo essay as our city weighs the future of the river in terms of development and habitat restoration. A sample:

Western Toad (Bufo boreas) — Perhaps no animal is as emblematic of the decline of native species in the decades following channelization as the western toad. One of the neighborhoods adjacent to the soft-bottom Glendale Narrows section of the river is still known as “Frogtown,” for the swarms of young toads and Pacific treefrogs that hopped through the streets each year until the 1970s. Today, toads and frogs are rarely to be found.
See you on the river, Jim Burns