Giant Oregon Grape?

Went for a nice walk with my sister and Salem at the arboretum today - it was brisk and cloudy but no rain. We passed by a huge specimen of Oregon Grape, we think, and it was full of hummingbirds. The bush/tree was at least 20 feet tall and just as wide and just brimming with chortling hummers. I tried to get one in a picture but they are just too fast. They were sucking all the nectar they could out of the hundreds of tiny yellow flowers. 

Then we wandered over on the bay-side of the park and were fortunate enough to see some otters who were hanging around the boardwalks. They poked up their heads and took a good look at Salem before curving back under the water. There were lots of ducks and geese in the water too. All of this is happening under and next to pilings holding up the 520 bridge - so lots of traffic noise. Those otters didn't seem to mind.