After a federal court in Michigan ruled Monday that it’s unconstitutional for cities and towns to put chalk marks on tires to enforce parking time limits, some municipalities in Maine may be looking into alternative methods to enforce parking limits this summer. Some larger cities in Maine such as Bangor and Portland enforce parking limits throughout the year, but for many smaller towns in Maine — especially along the coast — the availability of parking becomes an issue only during summer months, when the annual influx of millions of tourists and seasonal residents generates congestion along Route 1 and many downtown Main streets. Ellsworth Police Chief Glenn Moshier said Tuesday that he plans to look into alternatives for enforcing the city’s two-hour downtown parking limit before summer traffic appears in earnest. He noted that the ruling does not prevent the city from continuing to chalk tires but that he doesn’t want to continue using a method that unhappy motorists now will be more likely to challenge.