The three main activities at Galveston Island State Park are the beach, kayaking, and fishing. I did essentially none of them. I hiked what little I could and talked to the park rangers. I'd love to go back in summer for the main activities, but that means crowds. Even in the off-season, the drive down was jammed, and we sat in a long line of cars waiting to take the Galveston Island highway exit. Plan for traffic regardless of when you go.
Some of the other activities in the park include camping and birdwatching. I saw a few people out there, even in the bad weather, with binoculars looking for birds. I also saw multiple people fishing, if that is something you want to do. Most of them were fishing from near the kayak launch points. The biggest highlight that I got to experience, and the thing that made the drive worth it, was the wildlife.
There was plenty of wildlife, which was the highlight of the park, especially the seagulls, which are called Laughing Gulls (Leucophaeus atricilla). They reminded me so much of the Lava Gulls (Leucophaeus fuliginosus) from the Galápagos Islands. They both have the same unique dark coverage over their eyes. It was fascinating to see the similarities between this gull in Texas and the rarest gull in the world in the Galápagos Islands. Another amazing wildlife sighting here was the Roseate Spoonbill. It stands out with its vibrant pink color. Sadly, I did not get a great shot of this bird, but you can see the pink stand out among the darker colors of the environment.