10 November 2009
02 July 2009
A big lesson I'm learning in the field this year is that Northern Leopard Frogs are declining throughout their range, and generally their range is contracting from the edges in. Previously I had read that the species was declining in the west and apparently stable in the east, but I do not believe that is the case. Each regional field guide I read, and each local biologist I talk to, mentions that the species is declining locally, but it seems no one has put that together range-wide yet. They are declining locally, range-wide!
That makes the work hard for me, because I'm specifically sampling edge populations for my project. However, the edge now is, in most cases, not where it used to be. In West Virginia, the species only persists at one of the many historical localities. I spent two days there searching for leopard frogs, and found only one. Right now I'm in Rhode Island: I've spent two days searching in the area around Tiverton where there are several museum records from the 1980s and some sight records from the last few years. But this morning I talked to the state herpetologist (I finally got through to him - I've been leaving messages and emails for weeks) and he told me that the population here is probably extirpated, and that they only persist in one or two populations on the islands of the state. The story has been similar in many of the other places I've tried to sample lately.
While I can't say the frog sampling has been going well (I'd estimate I'm about three weeks behind schedule at this point), I am happy and healthy and safe. I've seen some great things, including many species of amphibians, reptiles, and birds I've never seen before. And I'm learning as much about the northern leopard frog as I expected to, even if most of that information is where it used to be.
In Kentucky the young leopard frogs were metamorphosing. I found it easiest to catch them at night as they were crossing the wet road.
25 May 2009
19 May 2009
I gradually worked my way south as I hoped for better weather. About mid-way through my second week, I heard frogs calling at night. What a relief – I had found them! I spent three more days looking for them at that spot, day and night, but I never saw a single frog there. I know they spend their winters underwater, and I wonder if they were still spending their days at the bottom of the ponds and only coming up at night to mate. The odd thing is that I never found any egg masses or tadpoles, either. I still haven’t. This is the big mystery of the year so far. Even when I know frogs are breeding, I can’t find their egg masses. This is a big disappointment, too, because it is much easier to catch an egg mass than a frog!
After a few days at that location, I tried Crescent Lake National Wildlife Refuge. This was a nice change of pace because the refuge manager kindly allowed me to stay in their researcher housing – a bed and a shower for free! Again I spent several nights hearing northern leopard frogs, and several days not finding them. I decided I needed a positive control to figure out what was happening, so I went back to a place where I had found frogs to be abundant last year. They were still abundant. It was a nice change to finally be catching frogs again! But I still didn’t know why I couldn’t find them elsewhere. A few things I noticed were that it was warmer here than the other places I had been looking, and warmer on that day than on any day so far on my trip. Also, although I could hear frogs calling at night here, I couldn’t find them in the lake where they were calling, and conversely I never heard any calling from the ditch where I was finding frogs. So, I think they’re just too hard to find when they’re breeding, and just then, in the first week of May, they were finishing their breeding and heading to their summer hunting grounds.
I decided to travel further southeast in search of frogs that were already active. (In spring in Nebraska, it is usually warmest in the southeast and coldest in the northwest.) What I found were lots of leopard frogs. Of the wrong species! It was exciting to find my first plains leopard frogs, Rana blairi (photo below), but the excitement soon turned into frustration when I couldn’t find any northern leopard frogs, Rana pipiens.
I gradually worked my way north again until I found a good population of northern leopard frogs. Once I found the right place, I was able to collect all 24 that I need in three days, but now I was two and a half weeks behind schedule. I cruised back west toward Crescent Lake NWR, and found another population of leopard frogs on the way. I was able to collect all I need there in three days, putting me only one week behind schedule instead of two and a half. Now I’m on my way to southeast Nebraska for my last stop in the state. This might be tricky because I need this to be an edge population, and in this part of the state northern leopard frogs and plains leopard frogs occur together. They are very similar, so I usually need to catch them to tell them apart. So, instead of just catching 24 frogs, I might need to catch 50 or so and throw half of them back! Wish me luck. . . .
02 April 2009
Camping is great, but I'm travelling alone and I don't have a lot of money, so I'll be looking forward to every chance to visit with friends or to crash on a couch or take a shower. So, if you're reading this blog and you know me, please take a look at the map below. Blue dots are places I plan on sampling this year (except for the dots in Arizona, Washington, and South Dakota, where I already have samples or I think I can get them from other people). I'll generally be travelling across the southern part of the range (roughly along the red line), then up into eastern Canada, and then back west across Canada. If you live near any of these dots and would like to hang out for a few hours, provide a place to crash, and/or help me catch some frogs (it's not easy, but it's fun!), then send me an email and let me know. I'll be looking forward to seeing you soon!
31 March 2009
This winter has been a great one for seeing crossbills in Utah, and around the United States. There was a big influx of White-winged Crossbills from the north, presumably in response to a failing spruce crop this year. But just recently, the Red Crossbills (like the one above) have shown up in big numbers down to the seed feeders. What is most surprising to me is how synchronous this arrival seemed. Around Cache County and even further south around Salt Lake City, people started reporting Red Crossbills at their feeders last weekend. Within days they were at the feeders of everyone I know who keeps a feeder. What caused this big change at the feeders? Did the local cone crop suddenly run out? Has a second big influx of crossbills, this time Red Crossbills, pushed down from the north? My guess is that it is both happening at the same time. One thing I've noticed is that at the same time Red Crossbills started showing up at feeders, I started hearing different call notes from them.
Red Crossbills have as many as nine subspecies around the continent that some people think should be considered full species. Each subspecies specializes on a different kind of conifer, has a different-sounding call note, and has a different shape to the bill that is adapted for the conifer on which they feed. Our local population has a very liquid "kip" or "quip" call that is relatively soft. In the last week, I've also heard a very dry, sharply-upturned "whit" or "swit" call from a crossbill type that is normally found feeding on Douglas-firs in the Pacific Northwest. I've also recently heard another call type that I cannot identify, but it has the same upslurred "quip" as our locals but calls more loudly and harshly, with less time between notes. So, although our cone crop may be getting low, I think we also have some new Red Crossbill visitors in town.
22 March 2009
I found a very interesting duck in Logan today, a "Brewer's Duck". The famous ornithologist John James Audubon described this species in 1840 on the basis of a specimen he collected in Louisiana. He mentioned that he had been unable to procure a second specimen, and that he thought this species was probably closely related to both Mallards and Gadwall. He was more right than he knew. We now know that this "species" is in fact not a species at all: it is a hybrid between a Mallard and a Gadwall.
I wasn't able to photograph the bird I saw, unfortunately. I got distant looks at it through my spotting scope, but as I moved closer to take some photos, it flew away to the south and out of sight. But, a very similar bird was found by Carl Ingwell and Jeff Bilsky less than an hour's drive from here on the Great Salt Lake exactly one week ago. (Photos of that bird are
This hybrid combination is rare, as are all hybrid combinations. It's the rarity of hybrids that keep species discrete from one another. However, ducks are famous (or notorious) for the amount of hybridization between species, relative to other taxa. For example, see this blog post for a series of beautiful duck hybrids, including the Brewer's Duck. My favorites are the Mallard x Red-crested Pochard, and the Mallard x Wood Duck. Keep an eye out for unexpected hybrid combinations at a pond near you. You never know what beautiful combinations might turn up!
26 February 2009
04 February 2009
In 2004 the American Ornithologists Union made a major change to birding in North America by announcing the split of what was formerly known as Canada Geese into two species. The larger of the two was to remain known as Canada Geese, and the smallest four of the eleven or so subspecies in the Canada Goose group would be known as Cackling Geese. This decision was based on genetic evidence that showed little to no interbreeding between these groups. This move was not unexpected by those who had been paying close attention to Canada Geese. The subspecies of Canada Gees were discernible in the field, and various subspecies or groups of subspecies had been elevated to species status in the past. However, it was a big surprise for most of the birding community, because, to be honest, most of us hadn't paid much attention to Canada Geese before.
In Utah, and probably throughout many parts of the U.S., this caused a stir. What was once one of the most common and familiar species in the state was now a pair of strangers. The safe thing to do in this situation was to assume that all previous records of Canada Geese applied to what was still known as Canada Geese, because the most common species here, the Great Basin Canada Goose, was still considered a Canada Goose. However, some records already existed of Cackling Geese in Utah, namely museum specimens. But the Utah Bird Records Committee decided to put the Cackling Goose on the state review list so that any records of this species in the state would be reviewed by a panel of experts.
Now that more people are looking for Cackling Geese, more people are finding them. In the four or five years since the species became a species, there have been over 20 records of Cackling Geese in Utah. However, I think the Records Committee must remain unconvinced, because few records have been submitted to the committee and even fewer have been accepted. Part of the problem, I think, is that the details of Cackling Goose identification were not well worked out. There were conflicting opinions on various websites about the traits that distinguish the largest subspecies of Cackling Goose (Like Taverner's Cackling Goose, seated at right in the photo above, and Richardson's Cackling Goose, in the back of the photo below) from the smallest subspecies of Canada Goose (like the Lesser Canada Goose, in the foreground of the photo below). Thankfully, I think that confusion will soon come to an end. A brilliant article published in the latest issue of North American Birds outlines in thorough detail how to tell the subspecies of Cackling Goose from one another, and from the smallest Canada Geese. I'm hoping that this article will be just the thing to help our knowledge of Cackling Geese advance in Utah and elsewhere. In the meantime, I intend to continue to submit records to the Utah Bird Records Committee until a pattern of occurrence has been established. Based on one year of actively birding in Utah, I think we will soon solve the mystery of the Cackling Geese and realize that this species, although rare, occurs annually in winter in Utah.