Last updated on May 11th, 2023 at 11:01 pm
Sunflower seeds have a tough hull, which accounts for 21% to 30% of the total weight. Since birds only eat the soft kernels of sunflower seeds and not the hard shell, they must first crack and remove the hull.
Birds crack and eat sunflower seeds by using their beaks. Several small birds use their toes to hold a sunflower seed as they strike the shell with the tip of their beaks to crack its shell. Birds with cone-shaped beaks crack sunflower seeds between the maxilla and mandible.
How Birds Crack Sunflower Seeds
All birds that can crack sunflower seeds have a technique that is primarily based on their biological characteristics.
To be more specific, the physical structure of their beaks.
The other aspects of cracking or eating sunflower seeds depend on the feeder and surrounding factors.
For instance, a bird can perch on a tray feeder or log to crack the shell.
But if you have a tube feeder, a bird will likely grab a seed and fly to a steady and safe perching spot nearby.
You may classify the main techniques used by birds to crack sunflower seeds into two categories:
- With the beak
- Inside the beak
Birds That Crack Sunflower Seeds With the Beak
All birds use their beaks to crack sunflower seeds. However, many species use their beaks as a striking tool.
They can’t break the tough shell or hull inside their beaks.
So, the following birds and many others crack sunflower seeds with their beak, such as:
- Blue jays
- Chickadees
- Titmice
- Woodpeckers
These four species use their beaks to strike and crack a seed’s shell. However, the cracking or eating techniques aren’t identical.
Take chickadees and titmice, for example, since both have a similar approach.
Chickadees and titmice select sunflower seeds from a feeder, but they often reject a few seeds before picking one with their bill.
Then, the birds perch on feeders and logs or fly to a nearby safe spot.
While perched, these birds hold a sunflower seed firmly with their toes.
Most chickadees and titmice hold the seed between their two feet and hit the hard shell or hull repeatedly.
They strike the husk with the tip of their beaks and flip the seed.
The striking continues on the other side until the seed is accessible. Eventually, they nibble or take small bites from the seed.
Most chickadees and titmice help themselves to several servings.
Blue jays have the same approach as chickadees and titmice, but they don’t nibble on the seed or take small bites.
Instead, they tend to eat a whole sunflower seed in one gulp. And they are likely to go for a few rounds to have their fill.
Sometimes, blue jays don’t turn over a sunflower seed to crack the entire shell.
They can pluck the kernel out of the seed after cracking and removing a substantial portion of the hull.
Woodpeckers also use their beaks as a tool, which is unsurprising given their enormous drilling prowess.
However, the species doesn’t hold a sunflower seed with its two feet, flexing its toes. Woodpeckers perch sideways on trees.
Here’s how woodpeckers crack sunflower seeds:
- They pick a sunflower seed from a feeder and place it at the corner of a tray or platform if one is available.
- Or they park a seed on a bark ridge of a nearby tree as their feet perch vertically along the branch or trunk.
- They hit the sunflower seed only a few times to crack the tough shell and gulp down the soft and tasty kernel.
- They don’t take as long as chickadees and titmice to crack a sunflower seed and can get to the seed very quickly.
Birds That Crack Sunflower Seeds Inside the Beak
All birds with a cone-shaped bill can crack sunflower seeds inside the beak.
So, they use the beak as a tool, but these birds don’t require the assistance of their toes or feet, except for some like parrots.
Here are a few birds that crack sunflower seeds inside the beak:
- Finches
- Cardinals
- Parrots
Finches and cardinals crack sunflower seeds using the following technique:
Finches and cardinals pick sunflower seeds in the same way as other birds, but they align the seed inside their beak, between the maxilla and mandible.
They then use their tongue to steady the seed and also rotate it when necessary.
They don’t need to hold the sunflower seeds with their toes or feet. Instead, they use the upper (maxilla) and lower (mandible) jaws of the beak.
As they crack some portions of the shell, they swirl or rotate the seed. The sharp edges of the maxilla and mandible crack the sunflower seed’s hull.
Finally, they throw the broken shell on the ground and eat the soft kernel.
Like finches and cardinals, parrots can crack sunflower seeds inside their beak, using the upper and lower jaws.
But they usually lift one limb to grab the broken shell with their toes so that they can extract and eat the seed.
Birds with cone-shaped bills may crack sunflower seeds with varying efficacy.
Some birds have an almost peeling effect inside their beak, while a few have a crushing impact.
In contrast, those that hit the shell with the tip of their beaks have almost an identical effect on the tough hull.
In the context of similarities, most small birds tend to eat sunflower seeds or kernels in bits and pieces, which is irrespective of the type or shape of their beaks.
Medium to large birds can swallow whole sunflower seeds in one gulp unless the kernels get crushed while cracking.
Also, seed-eating birds are somewhat picky during selection.
They may pick up a seed, shake it a little while holding it in their beak, and reject it before eyeing another.
This practice is partly why many feeders have some leftover seeds.
Furthermore, the cracking and eating techniques of some birds are rarely a neat process.
It’s common for parrots to lose a portion of the seed while maneuvering the hull with their toes.
So, you may find bits and pieces of kernels, along with cracked shells of sunflower seeds.