Activation energy is the amount of energy required to initiate a chemical reaction. The activation energy can be determined from reaction rate constants at different temperatures by the equation. ln(k 2 /k 1) = E a /R x (1/T 1 - 1/T 2).
Robins eat different types of food depending not only on the time of year, but even time of day. They eat earthworms early in the day and more fruit later in the day. Because they forage largely on lawns, they are vulnerable to pesticide poisoning and can be an important indicator of chemical pollution.
Juvenile robins and eggs are preyed upon by squirrels, snakes, and some birds, such as blue jays, Steller's jay, common grackles, American crows, and common ravens. Adults are primarily taken by Accipiter hawks, cats, dogs, and larger snakes (especially rat snakes).