Tuesday, February 25, 2014

Herons, Hawks, Parking and Bees - updated

Birds.  The Minto Bridge looks like it's all about birds right now.

As a prelude to construction this summer, a group of trees was just cut down, six months in advance of construction, in order to ensure Federally protected birds aren't nesting in them.  There's also an interesting note in Salem Weekly about the possibility that the Minto Bridge will disturb the heron rookery.

But perhaps the more interesting bit in the piece is on the prospect of not having to drive and park.

Worry about insufficient parking at the Carousel
Last year, before the "Park Parcel" was sold to the City suddenly last month, you may recall the furor over the parking lot and a proposal for access near the Carousel.

In the Weekly piece, one of the principals of "Pringle Square Access," the chief opponents to the apartments and State Street access, weighed on the Minto Bridge and its value to the community:
Salem ‘smart growth’ proponent Elaine Sanchez feels pets disruption will be minimal. She points out that Minto-Brown already has a leash law and the patrolling volunteers care very much that dogs are kept leashed.

“People will always break the law,” Sanchez says, “but you can’t say that’s reason to stop such enormous benefits to the entire community.”

Sanchez’s husband Alex points to the reduction of carbon emissions, saying, “the bridge will give people access to a beautiful trail system without having to drive to it.”
When some people argue, as they no doubt will, that the parking lot should be enlarged with some of the acreage of the park parcel, I hope that they will remember the way it was thought the "bridge will give people access to a beautiful trail system without having to drive to it." And I hope they will continue to give more thought to crossing the moat of Front Street, the Railroad, and the Liberty/Commercial couplet.  Will they support the Downtown Mobility Study's recommendations for two-way traffic and enhanced bikeways, especially on State Street as the main entry to the park? When there's a choice between implementing the two-way system with bikeways or expanding auto capacity, will they support better use of existing capacity?  A lot of advocacy right now is about saying "no" to things - but are there things to which we can say "yes"?

(Hint, hint - and, interestingly, a footnote on the Council Goals is to "Develop a streetscape connection on Court and/or State Streets to Riverfront Park to enhance access and visibility between downtown and Riverfront Park.")

Back to Wildlife

As for the herons, I have seen herons in the vicinity of Clark Creek, not far from Fred Meyer and the large intersection of Madrona and Commercial.

How disruptive really will the path be?
I have no expert knowledge of herons, but I wonder if they are more resilient and adaptive than we might think. They already contend with OR-22 across the river and concerts in the amphitheater. The path system from the bridge, as planned, will be far from the Audubon parcel on the peninsula.  I wonder if the fears are overstated.

It's certainly true that another set of large birds seem to be doing better these days - and doing so inside the city and rather urbanized parts at that.

Red Tailed Hawk at 12th and State
For a couple of weeks this fall there was a red tailed hawk that seemed temporarily resident at the corner of State and 12th and the Willamette campus. I saw it several times - I mean, I suppose it could have been different birds, but how likely is that! - during that period in trees and on street lights right on 12th.  (Have you seen it this winter? Maybe it hung out longer!)

Also in the past two years I have seen bald eagles, not just along the river, but in the city.  This fall I saw a pair gyring over the Blind School, Bush Park, and south over the lower field at South Salem High School and on towards Gilmore Field. Maybe expert birders and residents have seen eagles in the city even more often and over a longer period.

And there has been a resident family of sharp-shinned hawks near a very large institutional building, one that has large crowds of people, I have followed over the last few years as well.

It might be too much to say that big birds are doing well, but they certainly seem to be doing better, and they are adapting to the urban environment as they come back. The banishment of DDT has helped!

Instead of fretting over the herons, I suspect we would do well to turn those energies to fretting over invasives like ivy and knotweed, to driving less and walking more - and maybe most of all, to bees.  Pollinators.  We should probably be fretting a whole lot more about bees.

Update, early evening

In a comment, Jim reminds that over at N3B, they've been talking about a different bridge and heron rookery.

McLane Island also has a heron rookery
Hopefully this isn't just special pleading, but it sure seems like a large highway bridge would have a much greater impact on herons than a foot bridge and associated traffic. (See comments for more discussion.)

Update 2, Thursday the 27th

Criminy, I totally forgot I had a photo of a heron at Mirror Pond:

A real heron admires the statue heron at Mirror Pond
It's not from nesting season, but you'd think a heron disturbed by humans and human activity wouldn't hang out at Mirror Pond by the Civic Center.


Jim Scheppke said...

It does look like the herons on Minto are a good distance from the bridge and trails. However, this is what an EPA EcoRiskProfile report says about herons:

"Great blue herons are particularly susceptible to disturbance while nesting. Though response varies among sites and relative to the stage of nesting, nest site and colony abandonment can occur as a
result of human activities (e.g., logging, development) within 0.5 km. Some colonies or members of a colony can be easily disturbed early in the nesting season, and may even move or abandon the nest when people approach on foot to
within a few hundred meters (Butler 1992)."

Hope you saw that the NO 3rd Bridge Facebook page is also reporting about what sounds like a direct hit on a heron rookery.

Salem Breakfast on Bikes said...

Thank you! Hadn't seen the new N3B post yet, and forgot about earlier discussion. Thanks also for the EPA citation.

So, I've update the post with a reference to McLane Island - and then readers will have to decide how much inconsistency there is in this grey area:

Before funds were obligated, it was the position here that completing street and intersection connections to the Union St. RR Bridge should be a higher priority than a new bridge to Minto. This was not the priority chosen by Council and they pursued the Minto Bridge first.

Now that the Minto Bridge is a done deal, and the additional connectivity for the walking and biking public, as well as for downtown generally, will be an undeniably great thing, the scale of impact to the herons is not sufficiently large to be a reason by itself to kill the bridge suddenly.

Using the google, Riverfront Park looks to be only 200-300 meters from the bulk of the forested peninsula, well inside that 0.5 km mark. Though not separated by water, the path is farther from the trees than is the amphitheater. My hunch - and to be clear, I don't know this, so perhaps it is more wish than hunch - is that activities in Riverfront Park would have already driven off the birds sensitive to the disruption, and that the remaining birds are habituated to the Park will not find the additional path traffic a meaningful increment of additional disruption.

Contrarywise, the giant bridge and highway would have a vastly greater scale of impact to herons on McLane Island, and that is another good reason not to build the bridge.

Differences in the two bridge situations are not black and white, but I hope they are defensibly different shades of grey. Trying for the clarity of all-or-nothing doesn't seem helpful here. Instead,it seems to me there's a clear difference between a foot bridge and its associated foot and bike and even pet traffic skirting the bird refuge on the one hand, and a highway bridge that plows right across an island refuge on the other. It would be a loss if a belief that a large highway bridge would harm herons in one place necessarily entailed a full critique of a foot bridge and path in another place, and I hope the case for herons against the Minto bridge isn't that strong.

Laurie Dougherty said...

I've seen great blue herons several times in one of Boston's busiest parks (Arnold Arboretum) including last November when I was there; and in a remnant wetland tucked between Boston's Savin Hill neighborhood, I-93, a subway line (running on the surface there), a busy road and an office park. I passed this location often 20 years ago when I was taking classes nearby at UMass/Boston. And here's a very recent article about a great blue heron in the same spot:

But feeding and nesting are not the same thing. I found a set of guidelines online for protection of heron rookeries that describes a three-tiered buffer zone that is well under 1/2 mile. These are from the Vermont Dept.of Fish & Wildlife (borrowed from Maine DFW). The northern New England climate is very different from ours, so the nesting dates might be different, but the distance guidelines should be the same. (taking a quick and dirty look at a Google map of Minto zoomed at 1000 ft scale measure, the bike/ped path seems to me to be beyond the 650 ft secondary buffer boundary.)

Guidelines from Vermont DFW:
"Primary buffer zone: within 300 feet of the rookery perimeter:
There should be no habitat modification, such as timber cutting, land clearing, and construction of roads, trails, or buildings. Only actions deemed necessary for improving the nesting habitat should be undertaken. All human use of this buffer area should be avoided during the nesting period (15March- 1 August). Recreational activities such as hiking, hunting, fishing, biking, and camping are compatible with protecting heron nest habitat outside the nesting period.

Secondary buffer zone: from 300 to 650 feet of the rookery perimeter:
There should be no sand or gravel extraction, land clearing, or construction of permanent structures or roads. Existing farming operations including maple sugaring, and use of existing footpaths by non-motorized traffic are allowed activities which should not result in adverse impacts during the nesting period (15 March – 1 August). Activities compatible with protecting heron nest habitat outside the nesting period include: hunting, fishing, hiking, biking, camping, maintenance of existing roads or trails, and selective timber harvest.

Tertiary buffer zone: from 650 to 1300 feet from the rookery perimeter:
Construction of small buildings, temporary roads, or timber harvesting may be feasible outside of the nesting period with the consultation of a wildlife biologist or consulting forester. Activities such as hunting, fishing, hiking, and camping may occur in this zone."

Salem Breakfast on Bikes said...

Thanks for the info, Laurie! I think there's a strong case that the bridge and footpath will be on the outer edge of that secondary zone or outright in the tertiary zone. That zoning offers helpful clarity in the discussion.

It also underscores the N3B case on McLane island: The highway bridge would totally be in the primary zone.

(Also added a photo of a heron at Mirror Pond, which I think indicates some habituation to humans and human activity.)

Anonymous said...

Minto Island does not have a heron rookery. It hasn't had herons nesting for more than a decade.

Salem Breakfast on Bikes said...

Interesting! Are you connected with the Audubon folks? If there are no herons nesting there, then why are they worried about it and why are they talking about herons? Otherwise they're just trolling supporters of the bridge!