The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
Abstract. 1. We recently reported in this journal that the abundance of the migratory population of monarch butterflies is declining (Brower et al., 2011). Davis (Davis, 2011) subsequently challenged our conclusion.
2. Here, we provide further information about the increasing loss of larval habitat and how it may be contributing to the decline.
3. We also point out that Davis’s census data were obtained...
Abstract. 1. During the 2009–2010 overwintering season and following a 15‐year downward trend, the total area in Mexico occupied by the eastern North American population of overwintering monarch butterflies reached an all‐time low. Despite an increase, it remained low in 2010–2011.
2. Although the data set is small, the decline in abundance is statistically significant using both linear and exponential...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.