California officials are issuing an urgent plea to residents to report any sightings of monarch butterflies, as the state's iconic insect populations have dwindled to near-record lows. The California State Parks Foundation is encouraging Californians to document their observations as part of an effort to inform scientific understanding and conservation strategies.
The initiative coincides with California's Biodiversity Day, observed annually from September 5 to September 13, which celebrates the state's natural heritage. Participants can contribute by downloading the free iNaturalist app and uploading photographs of any monarch butterflies they encounter.
The data collected from these citizen observations will aid scientists in mapping butterfly presence throughout the year and will be crucial for the upcoming 30th annual Western Monarch Count. This count, which tracks the butterflies along the California coast, recorded approximately 12,260 monarchs in its most recent survey from late November to early December 2025. This figure represents the third-lowest tally since tracking began in 1997.
Western monarch populations were once in the low millions during the 1980s. The increasing frequency of record-low years has intensified concerns regarding the health and stability of the western monarch migration. Scientists estimate that by 2080, there is a greater than 95% probability of western monarchs becoming extinct.
Several factors are contributing to the significant decline in monarch butterfly populations, including habitat loss, the impacts of climate change, and the widespread use of pesticides. In 2022, the monarch butterfly was listed as endangered on an international level by the IUCN Red List of Threatened Species. While proposed as threatened in the United States, its precarious status highlights the urgent need for conservation efforts.