Baleen whales of the Northwest Atlantic live in a highly urbanized ocean. Their recovery from commercial whaling is impeded by anthropogenic risks from ocean industry, pollution, and climate change. Effective research, conservation and risk-reduction action requires near real-time knowledge of whale distribution measured using various methods including visual surveys from vessels or planes or acoustic surveys from autonomous platforms. The rapid collation and dissemination of whale detections and survey effort is critical but challenging given the number and variety of survey organizations and methodologies at work along the east coast of the US and Canada. WhaleMap (available at whalemap.org) is an open-source software system designed to meet this need. It automatically collates and displays results from all marine mammal survey teams on the east coast of the US in near real-time. It then exchanges these data with an analogous platform in Canada, called Whale Insight, to facilitate coast-wide coverage. It also interfaces with crowd-source reporting tools, such as the Whale Alert app, to incorporate observations from the public. In addition to being displayed online, WhaleMap data are distributed directly to regulators to inform management and are available for scientific and other purposes via request to the North Atlantic Right Whale Consortium (narwc.org). This presentation will give an overview of how WhaleMap works and provide examples of how it has been used to inform the conservation of the endangered North Atlantic right whale.