Like last year, temporary covers have been put over the entrance holes to keep House Sparrows out and to give the swallows a, literally, fighting chance to prevail over which species will eventually get to use them. The covers will hopefully prevent the sparrows from getting established before the arriving swallows have had a chance to feed, rest, pair off, take advantage of the growing insect supply and prepare to nest. The field will be assessed daily for the right moment to remove the covers
House Sparrow predation has been an ongoing issue. See previous blog posts on this issue ....
http://www.friendsofsamsmithpark.ca/2019/04/tree-swallows-and-house-sparrow.html
http://www.friendsofsamsmithpark.ca/2020/05/tree-swallow-nest-box-evictions-of.html
http://www.friendsofsamsmithpark.ca/2020/03/tree-swallow-boxes-now-ready-for-guests.html
We have noticed that seeds (rice, different grains, corn, commercial bird seed etc.) are quite often placed on top of the nest boxes, presumably in the mistaken belief that the boxes are feeding stations. This practice, along with putting bird seed on the large flat rock in the middle of the Swallow Field, draws in House Sparrows and is counter-productive to the Tree Swallow nesting project. If you witness this, please inform the person(s) who is doing this or just sweep the seeds into the grass below.
Terry Smith has created a video which gives a detailed look at the Swallow Field programme.