Sunday, March 11, 2018

Science and Miracles

Thanks to Grace Woodmansee for taking this photo! Despite all of the
lambing photos I've taken, I have very few of me assisting a ewe give birth.
Lambs at birth, like the offspring of most "prey" animals, are precocious; that is, they are quickly able to stand, nurse, and move off with their mothers. From an evolutionary perspective, this makes perfect sense. Sheep, especially lambs, are vulnerable to predators. Even before domestication, those females who had offspring who were on their feet and vigorous quickly were more likely to remain in the population and continue to reproduce. While domestication may have altered this ability to some extent, observant sheep breeders continue to include lamb vigor in their selection criteria (more on this below). As a shepherd myself, I have a tremendous appreciation for the evolutionary biology and genetics behind the ability of our lambs to get up and get going; I also find myself awestruck by the miracle of new life during each lambing season.

For the last 10 years, we have used an objective system to evaluate the maternal abilities of our ewe flock. Using the EZ Care system developed in the United Kingdom, we score each ewe at lambing on three criteria: lambing ease, maternal ability, and lamb vigor. Lambing ease assesses the ability of a ewe to deliver her lamb(s) unassisted. Maternal ability measures her ability to protect and keep track of her lambs (a ewe with twins, for example, must know how to count to two). Lamb vigor measures the ewe's ability to feed her lamb(s), as well as the lamb's precociousness. These traits significantly reduce our labor at lambing. A ewe must measure up to remain in our flock, and we only keep daughters of those ewes who measure up. An objective system like ours helps us avoid keeping a ewe simply because we like the way she looks - it helps us keep those ewes that perform well in our environment.

The foundation of our success with this system is the science of genetics. The traits that we're measuring are mildly heritable; that is, birthing ease, milking ability and maternal ability are at least partially inherited from one generation to the next. The environment, certainly, plays an important role - ewes on poor forage won't produce as much milk as ewes on good forage; however, the genetic predisposition to producing adequate milk is important, too.

Despite my understanding of the science behind these traits, I find myself marveling at the miracle of new life every year during lambing season. I find that I can understand the objective principles behind a ewe's ability to give birth, clean her lamb, and make sure that it nurses - and still stand in amazement while I watch it happen.

Part of this, I'm sure, is the fact that I directly participate in this process. On occasion, I have to help a ewe give birth. I'm often present when a lamb has its first taste of its mother's milk. Regardless, I don't think anyone - scientist or layman - can watch a ewe give birth; watch a newborn lamb shake the afterbirth from its ears; or watch an unsteady, 15-minute-old lamb find it's mother's teat for the first time - and not feel that they've just witnessed a miracle.

For me, this underscores the fact that scientific understanding and the miraculous are not mutually exclusive. My understanding of the "why" of sheep behavior doesn't diminish my sense of awe when I watch it in action. I've never understood the either-or perspective that permeates the debate between science and faith. Science, for me, is miraculous.

Here's a short clip of a lamb taking it's first meal - and here's a clip of a ewe delivering a lamb. You'll need Facebook to view them, I think.

Sunday, March 4, 2018

Of Sheepherders and Social Media

Like most farmers and ranchers I know, I keep a close eye on the weather forecast. My attention to impending weather is especially intense during lambing season - a stretch of cold, wet and windy weather creates challenges for shepherd and sheep alike. Last weekend, as we were just starting to lamb, all of the weather apps on my smartphone were showing significant rain and even a chance of snow at the end of the week. Since we lamb in our pastures (rather than in a barn), we knew we'd need to spend extra time and effort checking the sheep during the storm.

Thanks to a project I started two years ago (#sheep365 - I posted a photo of our sheep every day for a year on Instagram, Facebook and Twitter), I've become virtual friends with shepherds from all over North America and the United Kingdom. I've enjoyed comparing our production practices, learning from my colleagues, and sharing the often dark humor that comes with raising livestock (especially sheep). One of these colleagues, Jemma Harding (who raises sheep near Dorset, England, and who writes the excellent Me and Ewe blog) posted a photo of a lamb wearing a raincoat. (My UK friends have been grappling with some incredibly harsh winter weather this week - far worse than the rain and snow we've had). Intrigued by the rain coats, I sent Jemma a message via Facebook last Sunday evening. She told me that they were called Lamb Macs and were sold by Shearwell, an English company.

On Monday morning, I checked Shearwell's website and learned that the company has a US sales rep based in Minnesota. After a brief email exchange, I ordered a package of 100 Lamb Macs from England - and assumed it might take 2-3 weeks to receive them. Imagine my surprise when I received an email telling me they'd be delivered on Friday - less than 5 days after I'd ordered them! And this was despite the fact (as I learned via Twitter) that Shearwell's UK offices were closed immediately after I'd placed my order because of blizzard conditions.

I should probably describe these lamb rain coats. Lambs can typically handle wet weather if they can retain body heat. These coats are made from biodegradable plastic. They have a hole for the lamb's head and slits for all for legs. Once they're on, they look like a tiny horse blanket. The ewe can still smell her lambs' heads and bums, so she'll continue to let them nurse. When we tried the first ones on some new lambs on Friday evening, the ewes were puzzled by the rustling sound made by the coats - but they worked! Despite rain, sleet and wind overnight, the new lambs we'd blanketed came through the storm just fine!

All of this is not meant to be an advertisement for Shearwell (although I will say I'm VERY impressed with their customer service). It's also not meant to be an endorsement of Instagram, Twitter or Facebook. Instead, I'm amazed by the connections I've been able to make with shepherds in other places. I'm amazed by the opportunity to learn from, and share my experiences with, people who share my love for working landscapes and devotion to my livestock. In an era of heated online arguments, of trolling those with different view points, and of misinformation, maybe sheepherders are making the best use of social media!

Sunday, February 25, 2018

Anyone can be a Cowboy - Right?!

I live in a community where it's still kinda cool to dress like a cowboy (or a cowgirl).  Heck - even some sheepherders I know dress like cowboys. And some of us even have real manure on our cowboy boots! But when it comes to the actual work that real cowboys (and cowgirls - and even sheepherders) do, I've found that the clothes don't make the man (or woman). To me, it seems that not everyone has the skills necessary to herd livestock well.

I was reminded of this last week when I got a call from a neighbor asking if I knew who had cows in on a property just west of Auburn. The cows (heifers, actually) were out and were headed toward a major Auburn road. I knew who they belonged to, so I called the owner and told him I was available to help if he needed me. About 20 minutes later, he called and asked me to help - having had experience with my own livestock being out, I knew he was stressed about the situation. I also knew (because he told me) that the well-meaning neighbors who offered to help get the heifers back into their pasture were not actually helpful.

We were able to turn the heifers away from the road and walk them back down the irrigation canal towards their field. Once they realized we were going to "let" them go where we wanted them to go (as opposed to forcing them), they calmed down and walked quietly - until a well-meaning neighbor came out into the road and waved his arms to get them to turn (even though they were going where we wanted them to go). Arm-waving - and whooping and hollering - seems to be the extent of most aspiring cowboys' skill set. Stockmen (and women) - like my friend - on the other hand, understand the importance of releasing pressure on animals when they are doing the right thing. Reading livestock behavior - understanding what helps calm a cow or a ewe - is a crucial element of stockmanship. Working quietly, which helps reduce stress on the animals, is another important skill.

With the neighbor's "help," the heifers turned down another driveway (which wasn't where we were headed). We slowed the cattle down, and I held them in a corner of the fence while my friend cut a fence about 50 yards from the corner. Once he made an opening, I eased them along the fence line towards the opening. At this point, both of us were about 50 yards away from the heifers. They came to the opening and were slightly confused about why there was now a gate in what had been solid fence. Rather than force them through the gap, we gave them time to look around and realize that they wanted to be back in their pasture. One by one, they walked calmly through the opening.

Even some ranchers don't subscribe to the low-stress stockmanship techniques I've described - there are plenty of real cowboys (and sheepherders) who also whoop and holler. And I'll admit, I don't always get the technique right - I learn something every time I work livestock. To the uninitiated, low-stress stock handling seems slow, I'm sure - after all, neither one of us ran while we were putting the heifers back (nor did the heifers). Many folks wouldn't realize that we had control of the cattle from 50 or even 75 yards away - simply by moving into their flight zone (to get them to move) and then moving back out (to reward them for moving calmly in the desired direction), we were able to put them where they needed to go. In many ways, the job went quickly because we worked slowly and deliberately. I don't know that either one of us would consider ourselves cowboys, but I think we both aspire to be good stockmen.

Sunday, February 18, 2018

All Set Up and Ready to Go

Tomorrow - February 19, 2018 - marks the 142nd day since we put the rams in with the ewes. According to the principles of ovine biology, tomorrow is the earliest that this year's lambs could arrive. While I'm not certain that lambing 2018 will begin tomorrow, I am sure that some time in the next 96 hours, lambing season will get underway. The ewes have "bagged up" in the last several weeks (in other words, their udders have swelled with milk), and their bellies have "dropped" (a sign that their lambs are moving into birthing position). And so we spent today making sure we're ready for the onset of our busiest 6 weeks of the year.

These preparations began several weeks ago, when I went through our lambing kit to make sure we had the supplies we'd need. I checked our inventory of lamb ear tags - the 125 or so we had left over from last year should be enough. I purchased elastrator bands. Every lamb will have its tail docked; most of the ram lambs will be castrated - all within 24 hours of birth. I made sure we had enough scourable marking paint - single lambs are marked with their mother's ear tag number in blue; multiples (twins or triplets) get mom's ear tag number in red. And I made sure we had a good supply of iodine for dipping navels and vitamins for treating any weak lambs. Finally, I set up our Write-in-the-Rain lambing journal - we record birth date, maternal traits, and a variety of other parameters for every lamb.

Today, after we moved the ewes to their last pre-lambing paddock, we set up the first lambing pasture. We try to save pastures with plenty of tree cover and other natural shelter for lambing. As a pasture-lambing (as opposed to barn-lambing) operation, we pay close attention to the weather forecasts during our 6-week lambing season. Tree cover, brush, and other wind- and weather-breaks can be critical during a cold storm. The pasture we built today, at 7.74 acres, should last the "drop bunch" (sheepherderese for lambing ewes) for 5-6 days. But sometimes, lambs need a little extra help. We also parked our gooseneck stock trailer nearby just in case we need to "jail" a ewe and her lambs. By jailing, we simply mean putting a ewe in a small pen to make sure she bonds with her lambs - and to provide a space with a bit more shelter than the trees and brush can provide. We don't use this often, but we want to be ready.

Moving ewes with new lambs can be a bit chaotic. Lambs don't know the routine; ewes are reluctant to leave their lambs even though they know we're moving them to fresh forage. Because of this, we don't do any long-distance moves during lambing - rather, we drift the sheep from one paddock to the next. In our operation, this takes some planning; we don't want to run out of forage into which we can drift the drop bunch. For the next 6 weeks, we'll need about 60-70 contiguous acres for lambing - all of our grazing since December has been focused on making sure we have this forage available now.

And so now we wait. These next couple of days, for me, are like the week before Christmas. Beginning tomorrow (Day 142), we'll check the sheep 2-3 times per day. Depending on the weather, we might also check them at night. With the drop bunch about 7 miles from our home, this means 2-3 trips (usually first thing in the morning, around lunchtime, and before sunset). Sometime in the next couple of days, I'll notice that the guard dogs don't greet me when I drive up to the pasture - and that's when I'll know that lambing has begun! For now, we're ready to go!

Saturday, February 10, 2018

Paper Drought or Real Drought?

I recently read an article entitled, "Time to Get Rid of Two Outdated Water Words: 'Drought' and 'Normal'" by Tom Philp. Once upon a time, Mr. Philp wrote about water policy for the Sacramento Bee (way back when I worked for the California Farm Water Coalition). He's since gone on to work for the Metropolitan Water District of Southern California (MWD); I've become a small-time shepherd and a farm advisor who works with ranchers. Our respective professional evolution, perhaps, explains a difference of option, at least about the meaning of the word "drought."

Mr. Philp writes, "In California, a drought only happens when a governor declares it to be so." From a public policy perspective, this may be true. An official drought declaration requires water agencies to take specific conservation actions. In the artificial environments we've created in our modern cities, I suppose the average person isn't impacted by drought until their water supplier requires them to use less water. Drought doesn't hit home until your waiter doesn't automatically bring you water at your favorite restaurant.

I appreciate the point that Mr. Philp goes on to make - that California has been drier than "normal" two years out of three since 2000. I'll come back to the word normal in a moment. Because we seem to have entered a prolonged "semi-drought," (Mr. Philp's term), he argues that we should always focus on water conservation. I concur; the conservation habits that we adopted individually and collectively during the 2012-2015 should be permanent behaviors.

The word "normal," as it is applied to weather and climate, is interesting to me. Normal, in this sense, has several meanings. From a statistical perspective, normal is synonymous with average. Many of us, myself included, also use normal to describe our future climatological expectations based on past experience. As I think about normal in terms of averages, I see Mr. Philp's point. In the 15 years I've kept precipitation records in Auburn, our average annual rainfall has been about 32 inches. If I take the average between the driest year and the wettest year in that period, our average is over 40 inches. Only once in the last 15 years has our actual rainfall equaled the average.

In terms of my own weather expectations, "normal" has become a less useful term as well. In 11 out of the last 15 years, our total precipitation has been below the mean - less than 32 inches. From month-to-month and from year-to-year, we seem to be experiencing more extremes (both of dry periods and rainfall). For example, in December 2015 we measured just 0.01 inches of rain in Auburn; in December 2017, we had 14.53 inches. I'm not sure what normal is anymore!

But while I can happily give up using the word normal to describe our weather and our hydrological conditions, I can't give up the word drought. As a rangeland livestock producer, drought has a direct impact on me regardless of any governor's official action. As I wrote in a paper I co-authored with a number of colleagues, "In fact, rangeland livestock ranchers were among the first affected by the abnormally warm, dry winters at the beginning of the current multiyear drought." To read the entire paper, see Coping with Drought on California Rangelands. As a sheep rancher, I rely on fall rain to germinate the grass that my sheep will graze in the winter. I rely on winter rain to keep the grass growing as my ewes begin to lamb. And I rely on spring rain to grow the grass that we'll come back to in the fall. I also rely on the fact that rain in the Sierra foothills means snow in the high country; our summer irrigation supplies depend on winter snow (see Grass, Water and Warmth for more details).

Because of the lack of "normal" weather over the last 15 years, drought figures into our annual and long term plans. We have far fewer sheep than our grazing land could support in the best years to be sure we're ready for the worst years. We maintain a list of sheep we would sell if the grass didn't grow. We've invested in equipment that allows us to haul drinking water to our sheep, and we've upgraded our irrigation system to make sure we're using water as efficiently as possible. In the wettest year on record (last year, we measured over 62 inches of rain in Auburn), drought entered into our annual planning process - even though Governor Brown declared the "drought" to be over.

As we move into an era of increasing climate uncertainty, I agree with Mr. Philp that water conservation should be the rule rather than the exception. We shouldn't wait for an official drought declaration to begin saving water (whether we're in an urban area or on a ranch). For me, however, drought is not an abstract concept. Regardless of a politician's signature on a drought declaration, drought for me is when the rain and snow don't come. As a rancher, it will remain a part of my normal vocabulary.

Monday, February 5, 2018

Old Man Reno

Reno came to us as a 6-month-old puppy from a goat producer above Nevada City in 2008. In his first several years with us, we wondered if he'd ever grow up. He'd chase sheep and chew on lambs' ears whenever he got the chance. Fortunately, by the time he was 2, he'd figured out his job - and he's since become the best livestock guardian dog we've ever had.

As a young adult dog, Reno began to take the job of protection seriously. Not only did he protect the sheep from predators, he took it upon himself to keep an eye on our daughters when they were with me at the ranch as well. If someone Reno didn't know showed up, he'd be sure to place himself between the girls and the stranger. I could always tell when the ewes had started to lamb - rather than come to eat his dog food, he could be found watching over the lambing ewe. He never stole lambs, but he'd always make sure everyone was alright.

Like all working dogs (and like all people, I suppose), Reno has his quirks. He's offended by cats and raccoons (much to their detriment). He's the boss dog - sometimes he won't let the other dogs drink until he's gone off to nap. If he gets out of our electric fence (which only happens if there's a problem with the fence), we can forget about catching him - he always comes back, but on his own terms. If we call to him and chase him, he runs away - I suspect he'd extend a middle finger if he had one!

And yet despite his aggression towards predators big and small and his desire to roam when he's out of the paddock, he's a gentle soul. When I walk him on a lead, he walks beside me and leans against me. He's been known to let lambs climb on him. He has the most peaceful eyes of any guardian dog we've owned.

This is his tenth winter, and his age is showing. He's stiff in the morning (we're starting to give him glucosomine for his joints). He sleeps during much of the day. I think this will be his last lambing season - we've put Bodie with him with the hope that he'll learn from the best. I suspect that Reno will correct Bodie if he behaves inappropriately towards a new lamb or a lambing ewe. With age, however, Reno has also grown in knowledge (don't we all hope to do so?). Last weekend, I needed to put him in the back of the truck to take him to another ranch. He used to jump in the truck readily; stiff hips have made jumping difficult. As I climbed in to the bed of the truck, he watched me step onto the bumper and then the tailgate. He did the same thing, putting his front feet on the bumper. He then let me climb down and lift his rear end into the truck.

I know I've said this before, but I find it difficult to explain my relationship with my dogs to someone who has never relied on a working dog. As with any partner, I can sometimes be annoyed with Reno (and I'm sure he gets annoyed with me). I've loved pets; I think my relationship with my working dogs (herding and guarding) goes far deeper. Simply put, I respect them. I'm constantly amazed by their intelligence and dedication to their work. We share affection, certainly; we also share a love for our livelihoods.

Monday, January 29, 2018

Sheepherder CSI

About 10 days ago, while I was making my morning check of the breeding flock and feeding the livestock guardian dogs, I came upon a ewe (one of our daughter's) who was obviously not doing well. She was off by herself (which our sheep typically do only when sick or giving birth). As I watched her lay down from 75 yards away, she looked uncoordinated. When I approached her, she failed to get up and move away - and when I did get her up, she staggered a few steps and fell over. This prompted an immediate call to the veterinarian (who also happens to be my wife). As the ewe was only about a month away from giving birth, Sami decided to come check on her. We determined that she had a fever, and Sami noted a fair amount of nasal congestion. We also noticed that she was turning her head to the left and grinding her teeth. While Sami couldn't be certain, she suspected a combination of an upper respiratory infection and perhaps ovine polio (caused by a Vitamin B deficiency). Sami treated her and we slowly walked her up the hill to the corrals, where we left her in a pen by herself. Later in the day, Sami checked on her and reported that she seemed about the same. We decided we'd haul her home so we could watcher more closely. By the next morning, she was dead - as were the two lambs she was carrying.

When we experience an unexplained death loss, especially this close to lambing, we often take the dead animal to the California Animal Health and Food Safety (CAHFS) Lab at the UC Davis School of Veterinary Medicine. Not only is it cheaper to have an autopsy performed on a dead sheep than it is to have the rendering company remove the animal, we often get valuable information. In the case of this particular ewe, we found out that she died of an unusual case of meningitis (a rare condition in mature sheep). While we were reassured that she didn't have a condition that was likely to spread to the rest of the flock, an additional (and unrelated) finding did concern us. In checking her liver for heavy metals, the pathologist at CAHFS found that she had elevated copper levels (she had 260 ppm of copper; the high end of normal is 100). Copper is an essential micronutrient for sheep, but excess copper can be extremely toxic. Sheep store copper in their livers. When sheep undergo some type of stress (like a difficult lambing, harsh weather, or abrupt change in diet), their livers shed this copper into their bloodstream, often with fatal consequences.

When we read the results, we obviously became concerned about the copper levels in the rest of the flock. If this ewe had elevated copper, it was entirely possible that other ewes may have elevated levels as well. If so, we might have problems during lambing. Sami and I, along with our partner Roger, immediately went into Sheepherder CSI detective mode. Roger and I began researching possible sources of copper, as well as potential treatment options. Sami and I made plans to draw blood samples from a subset of the ewes.

Fortunately, I also placed a call to a friend who is on the faculty at the Vet School. Dr. Bret McNabb is a very experienced and knowledgeable large animal clinician and teacher. He told us that blood tests would not be a good indicator of copper status - we'd need more expensive liver biopsies. He also told me that he usually didn't see copper-related deaths until liver levels were above 400 ppm. He encouraged us instead to continue looking for potential sources of copper in our flock's diet, and to send any additional fatalities to the CAHFS lab. We also talked about treatment options, which included providing supplemental molybdenum to bind the copper that the ewes had already stored.

With Dr. McNabb's reassurance, we turned our focus to sources of dietary copper. We have a couple of suspects:
  1. The annual grasses that feed our sheep this time of year likely have some copper in them. Roger went back through some forage tests from the Sierra Foothill Research and Extension Center and found that at some times of the year, the forage may contain slightly more copper than the sheep need.
  2. For at least half the year, our sheep graze on land that was once in orchards. Copper sulfate may have been used as a dormant spray on this land; we may have residual copper in the soil. Our next step will be to test the forage for copper during the grazing season (spring, summer and early fall).
  3. We utilize surface water  to irrigate our summer pastures and to provide drinking water to the sheep during most of the year. To control algae in their canals (which can clog our sprinklers), our water agency uses one of several aquatic herbicides in which copper is an active ingredient. While both products are labeled as safe for livestock consumption, this may be something we need to investigate further.
  4. As Dr. McNabb pointed out, sometimes feed manufacturers make mixing errors. For example, the mineral mix we provide to our sheep does not have any added copper. However, mistakes can happen. This weekend, we sent a sample of our mineral mix to CAHFS for analysis. We should know the results by the end of this week.
  5. The weed common groundsel (Senecio vulgaris) contains a liver toxin that apparently inhibits the liver's ability to metabolize copper. We know we have common groundsel in areas where the soil has been disturbed, and we know the sheep will graze it on occasion. However, according to Toxic Plants of North America (Burrows and Tyrl 2001), sheep and goats are less susceptible to common groundsel than other livestock - and can actually be used to control it. Not exactly a smoking gun...
For now, the source of copper remains a mystery. The rest of the flock seems healthy, so we're hopeful that this ewe's copper levels were an anomaly. We'll definitely investigate any subsequent death losses - we're fortunate to have the CAHFS lab close by. And we'll continue to investigate the potential sources outlined above. Stay tuned.... And if you've had similar experiences with your sheep, please let us know!