Chipping sparrows and red cardinals could be holding up the Lansdowne Park redevelopment plan but the city believes work will restart today.

Some 60 trees were scheduled for removal to allow work crews to move the Horticulture building to a spot east of its current location. A small protest on Tuesday halted the work.

The Canadian Wildlife Service distributed an email to Holmwood Avenue residents on Friday, informing them they have documented evidence of some migratory birds nesting in the trees.

Because of that, the wildlife agency said tree cutting will have to be put off until later this summer, when the birds move on.

The email also said two wildlife officers will head to the site early Monday morning to "ensure compliance with the Migratory Bird Convention Act."

City manager Marco Manconi said Environment Canada officials visited the site Friday but it was determined the work did comply with the Act.

Work is scheduled to begin this morning and Manconi added the contractor's biologist and Environment Canada officials will be on the site to ensure "the execution of the tree removal plan is in full compliance with the Act."

Any delay could be a costly setback for the redevelopment project, which is working within a specific timeframe to get CFL football up and running.