I am thrilled to have found Kaeli Swift, PhD, who has extensively studied Corvids, especially my favourite, crows.
“A new study published in The Condor by Dr. Andrea Townsend et al. examines the relationship between urbanization, junk food, and the body conditions of crows. To conduct this study, her team blood sampled 140 wild crow nestlings along an urban to rural gradient. They found that plasma blood cholesterol levels increased in correlation with the amount of impervious surface, which is a typical way we measure urbanization. This finding suggests that crows in the city have more access to high cholesterol foods and they make haste in gobbling it up.
“Correlation is not causation, however, so to confirm this, they ran an additional supplementation study where they provided 10 rural crow parents with 3 McDonalds cheeseburgers 5-6 days a week, and then looked at how their nestling’s blood cholesterol levels compared with unsupplemented nestlings from the same area. They found that eating cheeseburgers most days of the week had a demonstrable effect on the subject’s cholesterol levels.
[…] “In the final piece, they examined the body condition, and 2-3 year survival of the 140 nestlings sampled along the urban to rural gradient. They found that cholesterol levels had no detectable effect on survival and were actually correlated with higher indices of body condition (meaning mass adjusted for size), a feature that is sometimes tied to higher reproductive success and survival.”
Here’s a few more entries on crow nutrition:
“I enjoy feeding crows, what kind of food should I offer them? Dried pet food is among their favorite but a cheaper option is whole unshelled peanuts. They also love eggs, tater tots, meat scraps and other nuts.” My crows like steak, sausages, potatoes with sour cream or butter, and don’t like tomatoes or red cabbage.
“Crow curiosities: what causes white feathers? Diets low in protein may also contribute to leucism, as the amino acid lysine has been correlated with increased white feathers. This is supported by the observation that urban birds (who presumably have a diet lower in meat and protein) typically have more color aberrations than their rural or forested peers.” Our crow dad has one or two white feathers on his left wing. For breakfast yesterday morning, he and his family got some bits of slow-roasted veal shank.
Swift says, “science communication will forever remain a core part of my identity as a scientist and person.” I highly recommend this fabulous young woman from Washington State, especially if you share my fondness for Corvids.
I am also thrilled to have found Joy Kiddie, MSC, RD who does a “Science made simple” series about human nutrition. Here’s her latest: “The recommendation to lower the consumption of saturated fat in the diet to reduce the risk of cardiovascular disease (CVD) has been the central theme in both the US and Canada since 1977, and has been carved into our respective Dietary Guidelines since the 1980s.
“A newly published study published by the American College of Cardiology has found no beneficial effect on either cardiovascular disease (CVD) or death of lowering saturated fatty acid (SFA) intake and that saturated fat intake is actually protective against stroke. This reassessment of dietary saturated fat intake was based on a meta-analysis of randomized control trials (the strongest data available), as well as observational studies.”
Kiddie says, plainly, “Coinciding with the recommendation for people to eat less saturated fat and more carbohydrate as the main source of calories, we have seen obesity rates go from ~10% of the population in both countries, to 1 in 3 people in the US, and 1 in 4 people in Canada — with another 1/3 of people falling in the overweight category.”
Veal shank is very tasty, my families inside and outside agree.
Kiddie, J. (2020.) “American College of Cardiology: No Benefit to Lower Saturated Fat Intake.” From https://www.lchf-rd.com/2020/06/30/amcardiology-no-benefit-to-lower-saturated-fat-intake/?fbclid=IwAR0ZBQFl9TM-bdhn8y6bc0EF-ceKiW78-zUIIsCRMLqVFx-9CFfBXyFI7U0. Quoting Astrup A, Magkos F, Bier, DM, et al, Saturated Fats and Health: A Reassessment and Proposal for Food-based Recommendations: JACC State-of -the-Art Review, J Am Coll Cardiol. 2020 Jun 17. Epublished DOI:10.1016/j.jacc.2020.05.077
Swift, K. (2019.) “Dumpster diving is giving crows higher cholesterol—but does it matter?” From https://corvidresearch.blog/tag/crow-diet/ (Quoting Townsend AK, Staab HA, and Barker CM. 2019. Urbanization and elevated cholesterol in American Crows. The Condor page 1-20.)