has any effort been made to conserve this species?
Plans were made to establish a captive breeding program.
Golden-crowned sifaka
Plans were also made to establish a captive breeding program at the Ivoloina Forestry Station, now known as Parc Ivoloina. 
what is the golden crowned sifaka? It is a medium-sized lemur. where are they normally found? Daraina in northeast Madagascar. what do they eat? A wide variety of plants and seeds. who are their predators? fossa do they have any interactions with humans? It faces many significant anthropogenic threats.
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Golden-crowned sifaka [SEP] Conservation
As of 2008, only ten forest patches that could support viable populations remained, according to the IUCN. Only one captive population of golden-crowned sifakas has been represented in a zoological collection. Building on a successful record of maintaining a viable captive Verreaux's sifaka population, the Duke Lemur Center (DLC) in Durham, North Carolina, requested and obtained permission from the government of Madagascar to capture and export this (then) unknown species for captive breeding. Plans were also made to establish a captive breeding program at the Ivoloina Forestry Station, now known as Parc Ivoloina. In November 1987, during the same expedition that resulted in the formal description of the species, two males and two females were caught and measured.