Sometimes, the opportunities are out of synch with the gear. I'm not capable of maintaining a collection of gear that's capable of doing each type of photography at the highest level possible. A lot of photographers aren't but when they've got paying jobs they can rent what they need, especially if they're located in a big city.
At one time I had some long Canon L series telephoto lenses I used for bird and wildlife photography. I sold them to upgrade to full frame camera bodies which are more suited for events, landscapes, etc. I've now got a nice set of gear for that type of photography with the occasional sporting event thrown in.
Then, along comes a Bald Eagle nest I can walk to from my home. Until the leaves come out in May this will be an amazing opportunity to document the nesting pair and eventually the young birds. All I need now is the gear.
I'm working on it, although what I end up with won't be at the level I previously had at my disposal. At present, I'm using a Canon 7D body with an EF 70-300mm f/4-5.6 IS USM lens. The 7D is fine but ideally I need both longer focal length and better image quality. I can probably pull off one or the other.
In any case, here some 100% crops from yesterday morning with the setup I described. Eggs should be present really soon, which I'll know when the nest is never left unattended. Yesterday, they were both off the nest quite a bit.
Remember, to see the full size image, click on it and then click on it again.