Do Bluebird houses need a perch
Treat Bluebird houses like bird houses intended for all bird house birds, with no perch of any kind needed to assist Bluebirds, nor can it benefit you in anyway.
Bluebird houses don't need a perch as much as they don't need bells and whistles. Bluebirds can manage without a perch, whereas any kind of perch present can actually assist predators like cats, as it becomes a foothold. Remove the perch if present by cutting it off with zero stub length remaining.
Really, Bluebird houses are built or designed no differently than bird houses made for Wren's, Chickadees, Finches, Woodpeckers or Sparrows - with a perch of any kind never needed to assist them, or if its only for decorative purposes.
Perch present on bird houses is a sure sign the house could have other issues unrelated to a perch; like a too big entry hole size or the internal measurements are incorrect, with a Bluebird settling inside a specific size box.
Manufacturer's should know a perch only stands to be for decorative purposes only, thus won't serve the Bluebird occupants one little bit.
What a perch will do with it perfectly situated under the entry hole becomes, is become a handy foothold for cats, squirrels or raccoon's to gain entry - or if they have to reach inside the box, intent on killing anything inside for food.
Quality Bluebird houses will never be built with a perch, instead manufacturer's opt for a default predator guard which may never come in useful - but there's no harm with a guard being present at all times.
Where you place your Bluebird house is probably on a wooden post or tree trunk, of which predators can use the perch at any angle - not just from above - to gain access to the box, thus its vital no additional foothold is conveniently placed in the front.
On your part, you do have to clean out your Bluebird house come the fall, thus a perch will only become a snag as you do, which will probably lead to the dowel breaking.
If you bought the Bluebird house, then I would personally return it, whereas it could be easier to cut off the perch rather than going through the hassle of product returns.
No perch is necessary
Like all bird houses in existence to cater too mostly small common backyard bird house birds, the bird house shouldn't have a perch mounted to it.
In fact some bird houses belonging to birds of prey like Owls or Kestrels can have more of a porch rather than a traditional long dowel shape perch. With smaller birds though, a perch isn't needed at all, as small birds can be prey.
When you can utilize a perch attachment you must understand it serves no purpose other than assisting predators.
Bluebirds entering their bird houses have no need for a perch, nor is it likely to be used if it is indeed present on their house.
Perches aren't necessary for many of you, but in case of attracting predators to your yard, who are intent on hurting the Bluebirds in the box - then its imperative the Bluebird house goes without a perch, always.
What makes a Bluebird houses a Bluebird house is a bird house with no perch, the correct size entry hole... plus the box must be built in accurate internal dimensions.
Bluebirds manage without
You must of seen Bluebirds plus other favorite backyard birds clinging or perching on to the sides of walls, branches or bird feeders in your yard from time to time.
Well, much like a wild bird clinging on at an awkward vertical surface, Bluebirds can absolutely cling on to the side of a wooden bird house without assistance of a perch or any kind of platform.
Bluebirds can manage just fine without a perch in place thus the perch itself is made redundant.
Bluebirds may perch on it at times but for the most part it will be ignored; it could be the Bluebird who wishes to nest in your Bluebird house may deem the box to be unsafe with a perch mounted - or if not predators will sure take full advantage of it.
If your particular Bluebird house doesn't come with a perch attached to it, then great, because a bird houses shouldn't have a perch nor do you have to mount a perch to your Bluebird house for it to succeed at attracting birds to it.
Birds have evolved to cling onto side way surfaces with their unique feet, thus they can cling on a smooth wooden surface or indeed cling on to the Bluebird house entry hole.
Perch can be a killer
With Bluebird houses never needing a perch of any kind, its important to remember a perch can lead to something more sinister.
Perch present on a bird house can only assist natural wild bird predators accessing the interior of the box in question.
What will become a useful foothold, the perch can be used for squirrels or raccoon's too put a paw on to it, in order to reach inside the house. What they would likely be reaching for is the unhatched eggs - although the fledglings will be at risk also.
What is worse above anything else, are local neighborhood cats who will take full advantage of the perch, to lean on it in an attempt to get inside the bird house. Same applies to a Bluebird house tied to a tree trunk next to branches, or a birdhouse hanging from a tree limb - which will assist cats if this box is positioned at an upward angle.
Cats a resilient thus are likely to achieve their goal if given a perch they can rest on as they attempt to kill any Bluebirds inside their house.
If a perch was mounted just under the entry hole then of course all these animals and more can reach the occupants. What to put in place of perch would be what is a predator guard that is screwed or glued on, to keep out such nuisance animals.
Proper installed predator guard will take up the space of where a perch would normally go, and as a Bluebird house can always do with a predator guard mounted to it, to be on the safe side, there is no space for a perch of any kind.
Should remove any perch
Whilst its imperative you remove all perches on a bird house prior to being mounted on the correct positioned post or tree, it can be a bad sign if their is a perch present from the very beginning.
And that doesn't just apply to Bluebird houses either, bird houses with a perch that are intended for Wren's, Finches or Chickadees must all be chopped off.
First of all, the perch must go because its doesn't belong on a bird house where the occupants become trapped - whereby predators lean on the perch directly outside their entrance hole.
What is worse, any reputable bird house manufacturer should know not to mount any kind of perch on it, and they should be in the business of building bird houses long enough to know better.
If your bird house comes with a perch then there's the likelihood their could be other defects present on the box - as it would appear the manufacturer doesn't know what requirements a bird house must have.
Regardless, if there is a perch present on your Bluebird house prior to mounting it, then chop it all the way off.
Perch at a shorter length isn't safer than a super long perch, thus a perch must be cut off at any length it happens to be, as it continues to be an issue if left on.
Summary
To have a perch present on any Bluebird house is a sure sign the brand the house was made under, aren't qualified in developing bird houses for birds in the first place.
Perches are not needed by your Bluebirds nor are they likely to take advantage of it if it happens to by mounted under the entry hole.
With a perch present it won't assist Bluebirds anymore than if it wasn't there. Similarly, a perch can make it difficult on you as you go about cleaning and maintenance the box, with a perch only getting in the way.
Who really benefits with a perch present are one of a squirrel, raccoon or worse still, cats... who are intent on reaching for the eggs, fledglings or the adult birds. Perches aren't used as such for the occupants, but will be used as a foothold for predators.
If your Bluebird house is made by you, or at least a quality made Bluebird houses if bought - would likely to come with a built-in predator guard - with this guard likely to take up the space where the perch would otherwise be mounted.
Don't feel a Bluebird house does need a perch, because it absolutely doesn't one little bit.
In fact, if there is a perch present then its up to you to remove it fully be sawing it off or breaking it off fully with not even a stub remaining.