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What happens if my site is suddenly disturbed? (Mowed, sprayed, etc.)

Depending on where your MLMP monitoring site is and who owns/manages it, you may not always have control over what happens there. Sometimes a site at a public park is mowed unexpectedly, or a wildfire comes through and the vegetation is destroyed. In one instance a number of years ago, a volunteer reported to us that her site near a rail yard was significantly disturbed by a train that had derailed! Regardless of the nature of the disturbance, if something happens at your site that changes the structure or composition of the vegetation there, we want to know about it.

At the beginning of each year, when you are watching for milkweeds to emerge (and recording the date), you will log into your MLMP profile and update the ‘Site Description’ for your site(s).

While most sites don’t change from year to year, it’s important that we know when they do. For example, if you are monitoring a habitat patch near an agricultural field and a portion of the grassland you monitor is plowed under, the size of your site would need to be updated. Or, if you monitor a roadside site and a construction project begins there and prevents monitoring for the season, you should note that in the Site Description form.

The Site Description form also includes a section on management activities that may influence the vegetation on the site. These are things like mowing or burning, which can be used to enhance the quality of the plant ecosystem, but can also occur for other reasons that don’t enhance the site. Regardless of the intent of these activities, record them on the Site Description form.

For all disturbances at a site, including those that may have been planned, we want as much detail about what happened and when it occurred as possible. This detail should be documented in the ‘Notes’ for Activity 1 on the week which the disturbance was noticed.

Finally, if a disturbance prohibits you from conducting your weekly monitoring, please indicate this in the Activity 1 data form and still submit your entry for that week. You should not fill out the milkweed section that week, but instead note why you were not able to monitor the site that week. For example, “My site was freshly mowed and no milkweeds were left standing”. If the disturbance was such that you could still observe milkweed plants for monarchs, you should note the disturbance and conduct your weekly monitoring activities as usual.

Use your best judgement to determine whether or not a majorly disturbed site will be suitable for monarchs in the weeks following disturbance. Milkweed does tend to come back after mowing and burning, and could be monitored again when new vegetation grows (remember to document each week you checked but monitoring was not possible). If a permanent change is made to a site (e.g. it is plowed under or developed), document the final disturbance so that we know it is no longer an active site. This should be done in both the ‘Extra Notes’ section of the site description section and in the ‘Notes’ of the weekly monitoring section in the data entry portal.

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