Is vegetable oil harmful to birds?
Created | Updated May 19, 2003
I had a long correspondence with the Wildlife Trust over this in October 2002. There was a list of bird feeding tips in one of those bird food catalogues and one of the tips was not to give the birds food with margarine or vegetable oil. This worried me because I make the birds a treat in the winter, of flour and pure sunflower oil and anything else that's to hand like ground-up nuts, raisins, oats etc. The birds love it and it disappears immediately I put it out (moulded into balls and placed in fatball holders). I get through something like 10 litres of oil and 30 kilos of flour a month this way. I used pure sunflower oil because one of the main reason we feed birds so much sunflower seed is because they are packed with so much sunflower oil, which it's generally agreed is very good for them.
Anyway, I contacted the catalogue people, concerned that I might have been harming the birds all this time. They said they got the list from the Wildlife Trust, so I contacted them. They sent me a list of ridiculous answers that was a great relief to me because they clearly hadn't a clue why they thought vegetable oil was bad for birds. They said they'd got the list from the RSPB. They and I contacted the RSPB to see if that organisation had any better answers and they didn't. It seems that there's this traditional view that vegetable oil is bad for birds and today it's just handed down dogma. One of the other birdfood catalogues actually sells fat-feeder logs and pinecones packed with vegetable oil based food. I contacted them to ask their view on the RSPB's vegetable fat warning and they never answered. I contacted them 5 times and they were always waiting for a response from the manufacturer which never came.
Here's a sample of the correspondence/discourse:
WT to me: There is little or no energy value within sunflower oil. Me to WT: I'm no expert obviously, but I was under the impression that a food's energy value was measured in calories. I looked up the calorific values of sunflower oil, suet and lard and, according to my old diet sheet, sunflower oil contains 252 calories per ounce, shredded suet contains 231 calories per ounce and lard contains 250 calories per ounce.
RSPB & BTO to WT and passed on to me: The RSPB suggested vegetable oils may have an effect on the waterproofing of bird's feathers but could not offer any hard evidence. BTO advised me that nutritionists have suggested that vegetable oils may be harmful to garden birds, but they couldn't explain what effect this has. I apologise for the vagueness of this reply and I would suggest that to be on the safe side, you stop feeding the birds sunflower oil and switch to an animal fat, such as lard.
RSPB to me: Birds would never come across pure sunflower oil in a state of nature. Me to RSPB: This seems a most unsatisfactory explanation to me, because the chances of a seed-eater or insectivore coming across suet or lard in a state of nature must be almost as remote.
The WT did make one last big effort and set someone to combing through scientific papers. They found some scientific data that suggested that the process by which vegetable oil is extracted, damaged a small proportion of the molecules and experiments on mice showed it was bad for them. This study seemed to conclude that vegetable oil was bad for mammals in general and, based on that, it's we humans who shouldn't be eating it, not birds.
Anyway, I contacted the catalogue people, concerned that I might have been harming the birds all this time. They said they got the list from the Wildlife Trust, so I contacted them. They sent me a list of ridiculous answers that was a great relief to me because they clearly hadn't a clue why they thought vegetable oil was bad for birds. They said they'd got the list from the RSPB. They and I contacted the RSPB to see if that organisation had any better answers and they didn't. It seems that there's this traditional view that vegetable oil is bad for birds and today it's just handed down dogma. One of the other birdfood catalogues actually sells fat-feeder logs and pinecones packed with vegetable oil based food. I contacted them to ask their view on the RSPB's vegetable fat warning and they never answered. I contacted them 5 times and they were always waiting for a response from the manufacturer which never came.
Here's a sample of the correspondence/discourse:
WT to me: There is little or no energy value within sunflower oil. Me to WT: I'm no expert obviously, but I was under the impression that a food's energy value was measured in calories. I looked up the calorific values of sunflower oil, suet and lard and, according to my old diet sheet, sunflower oil contains 252 calories per ounce, shredded suet contains 231 calories per ounce and lard contains 250 calories per ounce.
RSPB & BTO to WT and passed on to me: The RSPB suggested vegetable oils may have an effect on the waterproofing of bird's feathers but could not offer any hard evidence. BTO advised me that nutritionists have suggested that vegetable oils may be harmful to garden birds, but they couldn't explain what effect this has. I apologise for the vagueness of this reply and I would suggest that to be on the safe side, you stop feeding the birds sunflower oil and switch to an animal fat, such as lard.
RSPB to me: Birds would never come across pure sunflower oil in a state of nature. Me to RSPB: This seems a most unsatisfactory explanation to me, because the chances of a seed-eater or insectivore coming across suet or lard in a state of nature must be almost as remote.
The WT did make one last big effort and set someone to combing through scientific papers. They found some scientific data that suggested that the process by which vegetable oil is extracted, damaged a small proportion of the molecules and experiments on mice showed it was bad for them. This study seemed to conclude that vegetable oil was bad for mammals in general and, based on that, it's we humans who shouldn't be eating it, not birds.
