Unsure how old my chickens are, do they look like they still need heat?

[goldensussexstateofmind]

You don't see or hear predators because you aren't outside at night with night vision glasses or with a game cam set up in your yard.
The type depends on what part of the world you are in. The suburbs of the US have more predators than most places. There are more raccoons per square mile in cities than in rural areas. Downtown Toronto is the #1 raccoon capital in the world.
There are 2,000 coyotes living inside the city of Chicago.
In St. Louis, foxes and bobcats have been sighted in the city. Mountain lions have been caught on game cams in the suburbs. Black bears have been sighted in the suburbs here.
That doesn't even cover neighbors' or feral dogs, opossums, weasels, mink, etc..
2 issues I can see are the ability of some predators to dig under the base and your use of chicken wire as the only barrier protecting your birds.
Raccoons and large dogs can go through chicken wire like it is butter. Chicken wire keeps chickens in but doesn't keep predators out.
Mink and weasels can get into a 1" opening.
There isn't much keeping dogs, coyotes, foxes, raccoons and others from digging under your pen. Worse yet is that some of these predators have good night vision and chickens are blind at night so they have no defense.
I am in a fairly heavily populated area of the suburbs. Over the years, I've lost lots of chickens to dogs, several to opossums, way too many to raccoons and over $3,000 worth of chickens to mink in the course of a week.

As I said I close their coop door at night so they are safe at night. The dogs are outside with them all day in our fenced yard. I also have a much larger dog so I doubt anything would get past them. Does this really not sound sufficient?

 

[Egghead_Jr]

Lock the coop door each and every night.

 

[ChickenCanoe]

As I said I close their coop door at night so they are safe at night. The dogs are outside with them all day in our fenced yard. I also have a much larger dog so I doubt anything would get past them. Does this really not sound sufficient?

Yes, it does, if they are locked at dusk. You just asked what kind of predators you should worry about since you live in the suburbs.

 

[Egghead_Jr]

By locked we mean a latch that is impossible for Racoon to use. Those spring closed, hook and loop latches work. Just a hook and loop or bolt latch won't stop racoon.

 

[Cheeping chicks]

yes, I recommend a heat lamp when it gets cold. I still give my adult chickens a heat lamp when our temperature drops.

 

[ChickenCanoe]

That's unnecessary and negates any benefit from having chickens unless it gets under -20F,