Cardinal (male)
A recent study found that, in rural
areas, the bright red of Cardinals was a good indication of their health,
including the abilities to resist disease and raise healthy young Cardinals. In
urban areas, however, that wasn’t true.
In urban areas (cities and towns)
color didn’t indicate Cardinals’ general health or future reproductive success.
In urban areas there are many plants that are “exotic” – derived from other countries
or regions. Birds that eat these may get a lot of pigment, but are not necessarily in good
health overall, because most exotic plants don’t contain much protein or fat. A good
example is species of honeysuckle: the exotic Japanese (or Halls) Honeysuckle doesn’t do much
for the health of local birds; but the
native Evergreen Honeysuckle (Lonicera Sempervirons) is avian “health food”.
Urban Cardinals also have access to
birdseed which is very nutrient-rich, but low in carotenoids (which produce
pigments).
Of course, other species, in addition to Cardinals, benefit from good food. My advice, if you live in an urban
area, is to continue to offer fresh birdseed and plant masses of native
plants that are mostly red or yellow, such as Lantana, Turks Cap, Salvia
Greggii and Cardinal Flower.
HOW DO YOU DO, MR. CROW Just like people, American Crows can recognize specific human faces. Even years after the encounter. Also, they can associate the humans with positive or negative feelings – such as “feeds good stuff” or “scares me”.
Crow’s intelligence has long been known, but their brains aren’t unusually large. It’s just that they use their brain well. (Humans only use about 10-15% of the brain)
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