I hiked around Blendon Woods recently, and some birds were still singing. Yes, you'd expect some Goldfinches to still be singing now, because they often won't nest until thistles are in-seed (since that's a favorite food for their nestlings). But it was more than that. Field Sparrows and Song Sparrows were still singing from all the fields, and Indigo Buntings were still singing from field edges. Wood Pewees gave their mournful call, a few woodpeckers were still drumming, and a nuthatch honked in the woods. Catbirds were still singing in the thickets. Even a few warblers were in on the action, with Common Yellowthroats singing from several fields and a Hooded Warbler singing lustily along a forest trail. This was August; what's going on?
What's going on is the business of multiple broods. Many bird species have found ways to squeeze 2 or more broods of nestlings out of a single nesting season. Not only is this a much more common phenomenon than we expected, it might even be increasing. Many of the birds that second-nest are among the most successful species locally. Let's do a little comparison. Quick, which species do you see more of during migration, Wood Thrushes or Veeries? The former is a common second-nester, and is more common than the single-nesting latter. What about Wood Pewees versus Great Crested Flycatchers? Not much of a comparison; Pewees are much more common, despite having open nests (versus better-protected cavity nests for Great Crested). How about Common Yellowthroats versus most other warblers? Yellowthroats are among the most common warbler migrants nowadays.
The sobering truth is that second-nesting is a good survival strategy. It pretty much guarantees that you'll have good odds of raising at least one brood to fledging, despite all the risks of predators and brood parasites. It's been a feature of human-adapted birds for a long time: Robins, Cardinals, Carolina Wrens, House Wrens, House Finches, House Sparrows all untied themselves from the natural cycle of one brood a year once they discovered that human yards had a steady supply of food throughout the Spring and Summer. Now, however, the trend has been for more 'wild' birds to follow this path. Some flycatchers and sparrows started showing reports of regular multiple-brooding 20-30 years ago, and other bird species seem to be following suit. Now nearly 50% of North American bird species are acknowledged to be regular multiple-brooders.
Is this a phenomenon that's truly 'new' or did we just miss it in earlier years. Hard to answer definitively, but there have been good birders in Ohio for over a century. Admittedly, many of them didn't pay much attention to common birds in August, often assuming that nesting was over. However, careful observers like Milton Trautman noted a lot of 'second broods' in many different species. But it was a noteworthy occurrence then, whereas it seems less so now. I was floored when I saw House Wrens and Hooded Warblers feeding fledgelings in late August a decade ago; now I'm not surprised because I've found it so many times.
Sometimes, though, the trend is very subtle. The Cornell Lab for Ornithology had to examine hundreds of records of nesting Eastern Bluebirds before it became clear that Bluebirds in the southern states were often rearing second broods (see: http://www.allaboutbirds.org/NetCommunity/Page.aspx?pid=1244. ) In fact, it would appear that lots of birds are showing the trend. Here's a list generated by a Wisconsin birder for common breeders in that state: http://bluebirdslaugh.blogspot.com/2008/09/how-many-broods-for-wisconsin-songbird.html. What's apparent from this list is that many of the birds that we hear singing through August - Wrens, Sparrows, Buntings – are exactly those species that most often second-nest. Anyway you look at it, second-nesting is an exciting new development for us as birders. We now can keep our breeding bird census 'eyes' and 'ears' running late into the season, and follow the evolution of second-nesting, as more birds make use of it. It not too often that we can see such a momentous shift right before our eyes...and ears.
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We have a love-hate relationship with our rivers. We want to control them, yet we want them to run free (as long as they don't flood us). With plans afoot to dismantle the low-head dams on several central Ohio rivers, we want to believe that we're returning these rivers to their 'natural' state. But is that actually the case? How will these rivers actually behave, and how will it affect their resident animals? We can look at undammed rivers to find out. Precious few central Ohio rivers are undammed, however; the Darby and the lower Scioto are pretty much it. The Darby has an unusual watershed in that it drains hardly any suburban areas and has been the focus of monitoring and protection efforts for decades. But the lower Scioto runs free from Greenlawn south to past Chillicothe, and its watershed is heir to much of the agricultural and suburban development that plague other central Ohio rivers.
One of the best areas to access the river south of Columbus is at Mackey Ford, a State Wildlife Area between Duvall and Commercial Point. Here the state has bought up a large chunk of low-lying farmland with riverfront. Most of it is old successional fields and small sloughs, but there is a large block of riparian forest along the Scioto. This June I stopped by for a while and hiked some of the riparian forest. The river was very high, and much of the forest was inaccessable due to deep flooded channels, but there were still lots of expected forest birds like woodpeckers, pewees, and Red-eyed Vireos. Along the edge of the woods, Catbirds and Yellow Warblers scolded, and at one spot I had a singing Rose-breasted Grosbeak, a rare bird in many other places but not here. I've been monitoring the birdlife at Mackey Ford on the lower Scioto for a decade. This was both to compare a lower Scioto site with the Greenlawn area, but also to see how a large river shapes its riparian corridor in central Ohio. I've visited here several times each spring-summer to make a census of the birds present, and have even tabulated results for the 2 OBBA2 blocks that span the area. I think we've got a few answers, and, as usual, they're not all what we expect.
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First, the river shows some dramatic swings in water level. Much of the Scioto watershed is 'hardened' by concrete or open fields that allow for increased runoff. This means that water levels can fluctuate a lot here. Some late winter or Spring flooding here is epic, with all of the surrounding floodplain inundated. Even in late Spring-Summer, the river can rise or fall tremendously, often over the span of days or weeks. The pictures show the same spot only 3 weeks apart this Spring. This plays havoc with the riparian plants. This is not the complex, multi-layered forest you see along quiet parts of the Darby. It's been stripped down to those plants that tolerate flooding. Trees need to reach a certain size to survive these floods, and they can rarely reach huge size without being bent, twisted, or swept away by the current. The forest at Mackey Ford is old, but not very tall. The understory plants are only those that can withstand or take advantage of regular, deep flooding.
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Does this affect the birdlife? Somewhat, but not as you might think. Certain high canopy birds, like Parula & Yellow-throated Warblers and ScarletTanagers, are rarely found here. But lots of edge birds are here, and good numbers of Willow flycatchers, Catbirds, Yellow Warblers, Common Yellowthroats, and sparrows seem able to thrive in this perpetually successional habitat. Certain edge birds rare in other central Ohio locations, like Rose-breasted Grosbeaks and Orchard Orioles, are rather regular here. Cavity nesters seem to have mixed success; small woodpeckers are abundant, but large woodpeckers (Pileated) and Prothonotary warblers are not here. They apparently need reliable cavities on predictable territories, and snags don't survive long here. In fact, you could say that this is an ever-changing environment, and those birds that can't quickly adapt to these changes don't do well here. It's also hard not to think that most un-dammed rural/suburban rivers in central Ohio might look a lot like this.
One of the joys of the Ohio Breeding Bird Atlas has been the way it's given us 'new eyes' to re-examine areas close to home. I've found lots of 'new' areas that had been sitting under my nose, but I'm not the only one. Margaret Bowman, a long-time resident of north Newark, started looking carefully at areas around there and was astonished by what she found. She focused on the corridor of the North Fork of the Licking River running from Utica down to Newark, and she started racking up startling diversity of birds. When someone finds great areas not far away, you want to see what the fuss is about, so I took up an invitation from Margaret to help her on some of these OBBA blocks.
We focused on blocks north and east of Utica, mostly along the southern boundary of Knox County. Here the north fork of the Licking meanders through a broad floodplain that has been converted to large farms. On the rising uplands on either side are blocks of forest and meadows interspersed with smaller farms and ranches. We focused on areas along Debolt Rd and Arrington Rd; the former ran through a series of forest blocks, while the latter cut across the wide fields of the valley.
DeBolt Rd's forest blocks had given Margaret a number of interesting warbler records, and we confirmed them and tried to find new ones. The woodlands are mostly older 2nd-growth Beech-Maple forest, and had lots of calling Pewees and Acadian Flycatchers, as well as singing American Redstarts and Hooded Warblers. It was almost like being in the Flint Hills or Hocking Hills, but without the deep valleys. We even heard the distinctive buzzy song of Cerulean Warblers in 3 different places. Also present were Yellow-billed cuckoo and Scarlet Tanager, as well as Red-eyed and Yellow-throated Vireos. Old meadows in various stages of regrowth added White-eyed Vireo, Willow flycatchers, Common Yellowthroats, and Field Sparrows. Many of the yard edges had Catbirds, Brown Thrashers, and House Wrens. Almost all of these birds were singing, which was impressive for late June. It looked and felt like an area further north in Ohio.
 june2010 019.jpg Arrington Rd is very different, with large open fields of corn, soybeans, or fallow weeds. Eastern Kingbirds fluttered from the lines, while Red-headed Woodpeckers flew between the few old trees around. In one field we re-located a pair of young Sandhill Cranes that Margaret had stalked over the past 2 summers. The were slowly marching across the field, pulling at weeds and the occasional insect. At another spot, we hiked down a railroad right-of-way to view a small pond formed by the railroad embankment. Wood Ducks and a pair of Mallards paddled behind a lose screen of old willow stumps, while kingbirds and Tree Swallows flashed over the water after insects. A Green Heron duo flew up and perched on the tops of stumps. Where Arrington crosses the North Fork, we could hear the loud squawking of a Great Blue Heron colony, but the leafed-out trees prevented us from seeing more than a few herons.
Why is this place so much more wildlife-rich than many areas closer in to Columbus and Newark? I pondered this question all morning, as we kept encountering new, interesting birds on what Margaret avowed was a modest morning. Some of it has to do with proximity to unglaciated areas, which are only a few miles to the east. Many of those forest warblers were likely emigrants from the larger forest blocks of unglaciated Licking, Knox, and Coshocton counties. Some of it, though, seems to be due to other causes. Unlike farms closer to Columbus, these farms and orchards don't seem pressed to maximize profits and farm every inch. There were lots of shrubby edges, mature woodlots, and fallow fields. We had several locals stop and ask about birds and wildlife, and the enjoyment and relaxed atmosphere was evident in their demeanor. Even the suburban style houses were on large, shrubby or forested lots. All of it hearkened back to a simpler, less hectic time; on several occasions, I felt as if I had slipped into a time warp. These people were enjoying life there and now, not hustling for a wealthy retirement in some other state. Perhaps this kind of 'retro-transformation' is what we need to help balance our lifestyles with nature. It sure works here.
Sometimes we rush by good birding spots without even knowing that they were present. In fact, most of you have driven by this park and never realized it. This forested ravine along lower Spring Creek sits in Blendon township just south of Westerville. It's one of the main parks for the neighborhood of Huber Village, and sits along the NW corner of the I-270/State 161 interchange. Despite it's location, however, the dense forest and steep ravine walls here cut out much of the road noise, and the place is a great spot for birds and wildflowers. Here's a map to help you find it.
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To access it, you need to take State 161 west from I-270 and turn right (north) at the first light (Buenos Aires Blvd.). Within a block, look for the small entrance ramp on the right leading down into the parking lot for the park. Don't be fooled by the ballfields around the parking area; once you walk past them on the paved trail (about 100 yards), you reach the edge of the forest. The creek bottom forest here is penetrated by a trail that starts from the end of the paved trail. After about 50 yards, the trail crosses a small bridge and splits into a loop. One leg of the loop follows Spring Creek along the bottom of the wide ravine, the other loop winds along the north lip of the ravine, almost into the backyards of the neighboring houses. All the way is through a lush riparian forest with a good mix of flowers and understory plants. You're a stone's throw from I-270, but you only hear the freeway at a few points of the hike. The ravine and forest are that good of a sound buffer.
 may-ejune10 021.jpg On this early summer morning, I hiked through the trails looking for forest birds. Right by the edge of the ballfields, I could hear the descending warble of a Sycamore Yellow-throated Warbler, appropriately enough from the sycamores lining the creek here. At the edge of the forest, Catbirds mewed and a Carolina Wren chattered. As I stepped into the woods, the sunny glare of the fields gave way to cool shadows, where the freeway noise was almost non-existant, replaced by the squeals of young chickadees and the sonorous songs of Red-eyed Vireos and the occasional sneezy call of an Acadian Flycatcher. I was on the alert for a Louisiana Waterthrush that had been singing along the creek here just 3 weeks earlier, but no luck today. I guess that it was either quiet or had moved on. The woods here have that feeling that almost anything could show up.
This park has a history of birding, since Lou Schultz and Charlie Bombaci started visiting it back in the 1980s. I started visiting it around 1998, and have revisited it many times to assess its wintering and breeding birds. The riparian forest holds many of the expected breeders – woodpeckers, E.Wood Pewees, Acadian and Crested Flycatchers, Red-eyed Vireos – and has been a prominent Cooper's Hawk nest area for all the time I've visited. Yellow-throated warblers nest in the sycamores along Spring Creek just below the ballfields (or along the edge of the Water treatment Plant across the street). Louisiana Waterthrushes and American Redstarts have summered here, but there has been no recent evidence of nesting. Migrants swarm through the area, and I've seen up to 50 species in a half hour visit in May. That's pretty good for a spot nestled close by a major freeway interchange. Never underestimate the power of forested ravines as wildlife havens in central Ohio.
As we turn in to late May, Ohio's birders start looking for special 'late' migrants. We avidly hunt for, and have fond memories of, elusive boreal forest birds making their brief stops here. A short list of these birds would include highly sought-after birds like Black-billed Cuckoos; Alder, Yellow-bellied, and Olive-sided Flycatchers; Philadelphia Vireo; Gray-cheeked, Swainson's & Bicknell's Thrushes; Cape May, Blackpoll, Bay-breasted, Connecticut, Mourning, Wilson's and Canada Warblers. Often a trip in late May – early June can be made memorable just by seeing 1 or 2 of these gems.
Why are they so rare? It's not that they're numerically scarce; each can be abundant on their Canadian breeding grounds. It's more about how they migrate. They're among the last Spring migrants (like many shorebirds), because they're bound for the northern part of Canada (also like many shorebirds). Most are obligate insect eaters, and they delay their migration presumably to avoid the late frosts that can decimate their food supply. So late do they migrate that some birders have taken to calling them “3rd wave”, to distinguish them from earlier temperate (1st wave) and broadleaf forest neotropical (2nd wave) migrants. Because their migration is so delayed, they are more prone to fly very long distances with fewer stops, so that they can overfly much of the continental U.S. on their way north.
Nightime flight call monitoring suggests that lots of these birds are passing over the eastern U.S. at night. Ground sightings are so unpredictable, however, that the birds must be fast flyers (passing over most of the U.S.) or great at hiding when they are grounded. Growing up in Florida, I rarely saw any of these birds as migrants unless we had a serious storm in mid-late May; then they could be found in spectacular fallouts, particularly in coastal forest patches. The same pattern holds here in Ohio. Bad weather forces them down, and they are much more common at our 'coastal forest patches': the migrant traps along the Lake Erie shore, like Maumee Bay, Magee Marsh, Sheldon marsh, and Headlands Beach. Overflights are so typical of these birds that they'll often be found at Magee Marsh or other Erie traps well before we find them in central Ohio.
How can we predict them and successfully look for them? Weather is obviously important; to maximize your chances you need to get out on cloudy or rainy mornings. If you don't want to make the drive to the Erie migrant traps, you'll need to be aware of these birds habitat preferences. Most migrants develop a keen sense of preferred habitat, sometimes as they migrate, and the 3rd wave is no exception. Their preferences may be even stronger because of their rush to breeding. Many of the 3rd wave birds have habitat preferences that help focus you for them. Olive-sided Flycatchers love dead snags around conifer trees (which is exactly the habitat they prefer in Canada), so conifer-rich sites like Greenlawn cemetery are good for them. Connecticut Warblers like moist thickets near water, while Mourning Warblers like 2nd growth edges of old forest cuts (like you often find in powerline or pipeline cuts). Gray-cheeked Thrushes are super-secretive in migration; even if they're grounded, they seek out the shadows of the densest thickets and are often given away only by their strangely harsh locator call, a soft 'kee-yerr'. Obviously, though, there is an element of chance in finding these birds. A mix of right weather, right habitat, and plain old luck can lead to a memorable sighting. That's part of the appeal of birding; you just can't predict what you'll find.
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