Diet is the most important issue which comes up on our message board each spring as newcomers arrive with rescued nestlings. New starling parents are often unsure what foods to feed baby starlings, as caring for a wild nestling is a brand new thing for them. So, on this page I would like to address some basics about starling nutrition as well as discuss the suggested dog food based diet commonly used for wild baby songbirds.
So, what do baby starlings eat in the wild?
Knowledge about the diet of wild baby starlings is crucial for all of us to have in order to raise healthy birds. So, exactly what do wild starlings feed their nestlings? Seeds, or fruits, or regurgitated foods? Well, we first need to remember that the majority of North American wild songbirds (passerines) feed insect diets to their babies in the nest, only adding other foods to the diet later. Starlings are no exception to this and feed a variety of insects — mostly softer invertebrates — to their nestlings. Even adult starlings eat a diet high in insects, rounding out their diets with fruits, etc. depending on the season. Starlings are omnivores yet because they eat a larger amount of insects than do most omnivorous birds, they are very close to being insectivores. Their dietary needs include animal protein, vitamins (especially vitamin A!), and minerals such as calcium, etc. Below are two interesting tidbits about starling nestling diets:
“Few birds are more voracious than young starlings, and it requires the most strenuous efforts of the naturally active parents to supply the constant needs of their offspring. More than 95 percent of the nestling’s food is animal matter, largely insects.” — Farmers’ Bulletin No1571
“Without seeming to care whether the benefiting farmer thanks him or reviles him, he hurries with jerky steps about the farms and gardens in the summer time, carrying more than 100 loads of destructive insects per day to his screaming offspring. ” — Carson, Rachel. “How about Citizenship Papers for the Starling?”, 1939
But why is a dog food mixture better than parrot handfeeding formula for rescued baby starlings?
We already know that starlings have different nutritional needs than parrots. But it seems to be a common assumption that ‘wild birds eat seeds therefore it is okay to feed wild baby birds foods which were made for parrots who are seed eaters’ (foods such as parrot handfeeding formulas.) Years ago one company stated on its product labels that its parrot handfeeding formula was appropriate “for all baby birds.” One company’s label recently still stated this last time I checked. Unknowledgeable pet store employees are still recommending parrot formula for wild baby songbirds. However, the fact is that parrot handfeeding formulas are specifically formulated for herbivores (birds who eat seed, fruits, nuts, flowers). Thus the main protein content in parrot handfeeding mixes is from plant sources. Plant protein does not supply adequate amino ac >[More about proteins farther down.]
To compare handfeeding formula and dog food ingredients, simply go to a petstore and read labels. What you will find is that the main ingredient in parrot handfeeding formulas is most often corn, followed by things such as wheat meal, oats, rice flour, plant protein products, etc. Next look at dog food labels, and notice not only the protein and fat level but also the main food ingredient. Some examples are below:
Zupreem parrot handfeeding formula is 22% protein with its main ingredient being corn, and the same is true for such formulas as “Kaytee Exact” and “Lafeber’s Instant Nutri-Start” (only two of many more brands). It is interesting though that Lafeber is the only company that tells you up front that it is not appropriate for insect eating birds. This is from their web site: “Instant Nutri-Start Is Not Meant To Be Fed To Insectivorous Birds Or Raptors.”
Some of the dog food brands that come closest to the ratio required by starlings of 33% protein and 12% fat would be: “Innova Puppy Dry Food” with 26% protein and 12% fat or “Purina One Senior Protection” with 28% protein and 12% fat.
Dog food would provide not only the animal protein needed for an omnivorous or insectivorous bird but also additional needed vitamins amd minerals. For more information about this, please see the info under the heading entitled, “Food for Baby Starlings” on the Baby Starling Care webpage.
Why is a certain type of protein so important to starlings?
First, a little about proteins in general —- Proteins are very important for normal growth in humans and animals. The building blocks of proteins (or what proteins break down into) are amino acids. Amino acids are important not only for growth but also for healing of tissues, for production of immune bodies and enzymes, for supplying energy, and for most chemical processes in the body. There are 20 or so amino acids. Eight of these cannot be made by the human body and are referred to as ‘essential amino acids.’ They must be gotten through foods containing them.
Proteins from animal sources supply the most amino acids and are said to be “complete proteins.” (Eggs supply all essential amino acids, and meats are high in them too.) Proteins lacking in some essential amino acids are said to be “incomplete proteins”, and these incomplete proteins originate from most plant sources. It is known that a lack of amino acids lead to deficiencies which adversely affect health.
The “biological value” of a food is one way of evaluating a source of protein. Biological value is “the measurement of the amino acid completeness of the proteins contained by the food.” The info below was taken from a biological value chart saved years ago off of the Internet, and it illustrates that plant sources are lower than animal sources in complete proteins. (Online searches yield more info about this.)
|Fish Meal 92%|
|Wheat Gluten 40%|
Animal protein is necessary for European starlings!
Different animals have varying amino acid requirements: herbivores such as rabbits will get all the amino acids they require from plants (or from incomplete proteins), whereas carnivores will get none of their essential amino acids from plants. Starlings are not herbivores, and studies have shown that animal protein is necessary in their diet. Below are a couple of quotes about the importance of animal protein to starlings (taken from The Starling by Christopher Feare –an invaluable book for starling owners to read!)
“Starlings spend most of their time feeding in grassland throughout the year. During the breeding season, and especially when feeding young in May and June, their diet consists almost entirely of invertebrates obtained from the surface or from the upper few centimetres of the soil of grass fields. Should this source of invertebrate food disappear for some reason, for example during a particularly dry spell, the chances of survival of the chicks are much reduced when they are given alternatives such as bread, cereals, and cattle food. This happened in 1975 at Worplesdon and it resulted in the total failure of all of the late broods. In addition to being presented with plant proteins, which are less readily asimilated than animal proteins, the absence of invertertebrates in the diet deprived these late chicks of practically their only source of water.”
“Most omnivorous birds eat invertebrates at most times of year and Berthold (1976) found that plant foods constituted a reserve that could be exploited when invertebrates were less readily available. The nutrient provided by the invertebrates is animal protein and its absence from the diet leads to weight loss and death (Berthold 1976). Only specialist herbivores such as pigeons and Waxwings are able to survive without this animal protein. The effects of the absence of invertebrate food on male Starlings were clearly shown by Al-Joborae (1979) who found that while the testes of birds fed on insects grew normally in spring, the testes of those Starlings maintained on a plant diet did not develop at all.”
Reference: Feare, Christopher. (1984). The Starling. pages 56-57 and 204-205
To feed or not to feed the suggested dog food diet?
Feeding an improper diet to wild baby songbirds results in unhealthy birds. Rehabbers learned through firsthand experience that feeding parrot handfeeding formula to wild songbird babies resulted in poorly developed feathers and poor weight gain. Some birds who were raised on it were unable to fly, while others died. We already know that wild baby songbirds need animal protein in order to develop properly, and that is where the dog food based diet comes in. This diet which is suggested on this website is one commonly used by wildlife centers across the country. In fact, when doing an online search about what to feed a wild baby bird, it is amazing how many wildlife rehabber sites show up listing variations of the dogfood diet or a cat food diet for baby songbirds.
Perhaps the thought of feeding baby birds a diet mixture based on a food formulated for canines may seem strange to new starling owners. But the dog food mixture has been found to supply the protein, vitamins, and minerals necessary for healthy baby songbirds. This diet has had very good success with thousands of birds under rehabbers’ care. Also, countless pet starlings, some whose owners post at the Starling Talk Message Board, have been thriving on this diet (supplemented with fresh veggies) for years. Until much more research has been done, possibly leading to a food formulated specifically for captive European starlings, it seems wise to stick with the dog food diet proven to raise healthy starlings.
Ultimately everyone will choose what to feed their own starlings. But before choosing a diet for a captive baby or adult starling, it is necessary to have a basic knowledge about the bird’s nutritional needs.
Where to find more info about diets for baby and adult starlings–
Please read the article, “Diet of the Wild European Starling”, for detailed information about starlings’ diets in the wild.
Info about the suggested diet for starling nestlings is at the following webpage: Starling Talk’s Baby Starling Care