Small groups of people and a man walking a dog keep their distance from each other on the Eastern Prom in Portland in April.

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Travel in Maine, which dropped significantly after the novel coronavirus was confirmed in the state, picked up again in the last week of April, though data suggest that much of the increase in activity occurred outdoors where the virus seems less likely to spread.

Cellphone data, collected anonymously by companies including Apple and Google, is one metric policymakers have used to estimate compliance with social distancing measures, though the data do not indicate whether people are following distancing recommendations by staying six feet from each other or holding large gatherings.

It does, however, provide insight on how frequently they leave their homes or visit certain destinations, showing that Mainers are following national trends in traveling more as business restrictions begin to lift. That could be explained by both cabin fever and nicer weather.

Mainers are going out more, according to several metrics. In mid-April, about 40 percent of Maine residents were not leaving their homes each day, according to an analysis of cellphone data by the firm SafeGraph. In the last week of the month, however, that fell to about 35 percent. The decline largely mirrors national trends. The percentage of people staying home each day peaked at 44 percent in mid-April before falling to 39 percent by the end of the month.

The uptick might indicate some weariness with continued restrictions. A poll conducted in the second half of April indicated that the vast majority of Mainers still supported maintaining current social distancing measures, including a stay-at-home order and business closures that have drawn two large Augusta protests within two weeks.

Mainers took slightly more trips to grocery stores and retail establishments in the last week of April compared to earlier in the month, according to an analysis of cellphone data by Google. Visits to those establishments were still down 13 percent and 36 percent, respectively, from a baseline earlier this year.

Warmer weather might be drawing more people outdoors, where transmission of the virus is less of a threat. In Maine, the types of destinations seeing the most dramatic increase in visits were outdoors. Visits to parks were up nearly one-third over a baseline from earlier this year, according to Google, potentially reflecting the warm weather seen in the last week of April.

Maine, like many states, initially closed state parks due to the outbreak, citing concerns about overcrowding and the spread of infection. However, most state parks have reopened under the first phase of Gov. Janet Mills’ reopening plan, though a handful of popular beach parks, as well as Acadia National Park, remain closed.

The state’s decision to reopen some parks came on the heels of a study in China which found that outdoor transmission of the coronavirus was relatively rare. Researchers identified only one outbreak that occurred outside, with two people infected, out of the 318 outbreaks detected.

That research is preliminary, though encouraging as Maine looks to resume economic activity while social distancing remains its primary mechanism for controlling the spread of the virus. A handful of states, including South Carolina and Louisiana, have allowed restaurants to reopen with outdoor seating only, while Maine still limits them to takeout and delivery.