riddle - Hunting Season is Open!

As some of you may have gathered, I really like learning about new animals; some of my favorites are:

Badgers, Octopi, Aardvarks, and Akitas

In the spirit of a good challenge with a chance to learn new things, I've created this multi-tier riddle that will give you all a chance to learn something about 5 different animals. To solve this riddle, you'll need patience. Each sub-riddle will be harder than the last; where the final riddle will prove to be difficult indeed as you'll need to get creative, and reflect on what you've learned.

I'll start us off easy with animal number one. Remember that each animal will be harder to find than the last and have fun learning!

Animal #1

I am heard of by many, but encountered by few.

Most humans fear me, but tis I who fear you.

I'm active all summer, and sleep until spring;

When I go and I wait, for food that flies without wings.

Animal #2

Where I am from, it is bitter and cold;

This is one reason, I won't get too old.

My home is a burrow, under the snow;

It's where I stay warm, until I must go.

All through the winter, I wander around;

To gather my food, I must not be found.

An interesting fact, on how I was born;

You used to believe, I came from a storm.

Animal #3

My children drink milk, as all mammals do; but as we get older, we forage for food.

Under the leaves, and into the grass; my species is known, as lightest in class.

Animal #4

There's no where to hide, and no where to run;

I can honestly say, this will be fun.

I'm known for my spots, and confused for another;

The first thing you'll think, is my bigger brother.

Round like a dish, my ears are distinct;

In order to find me, I'll force you to think.

I hope you enjoyed finding the animals above! I learned a few things along my path to creating these riddles, and it took a while to pick the animals I wanted to use.

The Hunt is Coming to an End

You've found all my brethren, this much is true;

T'was one who informed me, from which you need two.

I am as small as can be, but not small like three;

From this animal, six and eleven you need.

You'll need to see two, he has six and four;

And four has seven, but you need one more.

If you can find me, I'm one of a kind;

I resemble two animals, as I even have spines.

I'm one of five in my class, and three are my brothers;

Once we were born, we lived in our mother.

Nearly a year had gone by, but I moved on my own;

To search for a place, forever to roam.

Hint

You're looking quite hard, tis this I can tell; the point being numbers, on which you will dwell. When working with numbers, it may not be seen; that some of these numbers refer back to me.

Note: Though I would prefer for the fifth riddle to be solved with the answer explaining the pattern I hid within it, I will accept an answer that lists all five animals. If the accepted answer does not contain the pattern I used, then I will add my own answer to explain it.

As a final request, I would like to know what you thought of my riddles with your answer; did they make you think? Did you learn anything new? What did you find the most interesting?

Answer

Partial answer;

Riddle 1:

I would assume some species of bear. "I am heard of by many, but encountered by few. Most humans fear me, but tis I who fear you. I'm active all summer, and sleep until spring; When I go and I wait, for food that flies without wings." Bears hibernate and can be frightened quite easily. Wingless food... flying fish? (Through those are ocean creatures and not river food.)

Riddle 2:

A lemming. "Where I am from, it is bitter and cold; This is one reason, I won't get too old. My home is a burrow, under the snow; It's where I stay warm, until I must go. All through the winter, I wander around; To gather my food, I must not be found. An interesting fact, on how I was born; You used to believe, I came from a storm."

Riddle 3:

An Etruscan shrew. "My children drink milk, as all mammals do; but as we get older, we forage for food. Under the leaves, and into the grass; my species is known, as lightest in class."

Riddle 4:

A serval is my first guess,followed by: fishing cat, margay, marbled cat, black-footed cat, and perhaps a cheetah; round ears and spotted body, yet smaller than a leopard. "There's no where to hide, and no where to run; I can honestly say, this will be fun. I'm known for my spots, and confused for another; The first thing you'll think, is my bigger brother. Round like a dish, my ears are distinct; In order to find me, I'll force you to think."

Riddle 5:

building/copied from Linux's answer, using letters idea. Once I get a break at work I'll start cracking down on it!
Linux found "echidna tachyglossus aculeatus."
You've found all my brethren, this much is true; T'was one who informed me, from which you need two. Our first answer, second letter. bear

I am as small as can be, but not small like three; Tachyglossus aculeatus is the smallest of the echidnas
From this animal, six and eleven you need. Etruscan shrew, gives us C and H.
You'll need to see two, he has six and four; "two" (lemming) is holding onto the fourth and sixth letters of "echidna": "i" and "n".
And four has seven, but you need one more. d or a. Since we need two letters from this one and it must be a seven-letter word, it's not serval. I assume we'll need the seventh letter, and the last letter is one we will fill in as a guess to get "echidna". Mostly likely it is a d; leopard? Alternatively, it IS serval, and "four" (serval) is holding onto "seven": echinda.
If you can find me, I'm one of a kind; I resemble two animals, as I even have spines. Echidnas look like anteaters, hedgehogs, porcupines, etc.
I'm one of five in my class, and three are my brothers; there are four species of echidnas and one of platypus in the Monotreme order
Once we were born, we lived in our mother. Echidnas have a pouch
Nearly a year had gone by, but I moved on my own; Puggles will stay within their mother's den for up to a year before leaving
To search for a place, forever to roam.

I would like to know what you thought of my riddles with your answer; did they make you think? Did you learn anything new? What did you find the most interesting?

Some of the riddles have definite "eureka" words, but as you said- the riddles definitely get harder! After submitting first-round answers, they did begin to make you think for new answers. My only critique would be to think about your animal specifically, and what it could be mistaken for. Add details to the riddle to stop those potential answers- that way, an answer is wrong and not not what I was thinking of. I didn't know what the smallest rodent was until now :)