Observations by a Backyard Naturalist III: Insects

“Every kid has a bug period… I never grew out of mine.”

Edward O. Wilson

When we consider biodiversity, no single taxonomic group that we can readily observe comes close to the insects. The estimates of the number of extant species ranges from a low of 1.5 million to a high of 30 million, but the latest estimates point to about 5.5 million species (Stork 2018).   It should be noted that there is considerable uncertainty in these estimates because of under-sampling, e.g., northern Canada has been quite poorly sampled, and cryptic diversity, i.e., parasitic species are poorly known and difficult to study (Forbes et al. 2018).  There is no great surprise, then, that our gardens and homes are alive with insects and other arthropods. A recent study discovered hundreds of insect and other arthropod species in urban and suburban homes in Raleigh, North Carolina (Bertone et al. 2016). A similar survey in a single home in Toronto resulted in the discovery of 112 species of arthropods (The Great Wild Indoors). Taking all organisms into account including all three domains, Larsen et al. (2017) in an interesting paper estimated total species richness at between one and six billion (one billion = one thousand million). If you like me learned about biology many years ago, you might not recognize many of the different taxa now. Anyway, they concluded that insects

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Estimates of biodiversity by Wilson (1992), Mora et al. (2011) and Larsen et al. (2017).  From Larsen et al. (2017).

comprise less than 8 % of total diversity as do fungi and protists, respectively, while fully 78% of diversity comprise bacteria! Of all these organisms, we have named a measly 1.5 million or so, and with taxonomists seemingly declining so fast that they would likely be categorized as “Threatened” by the International Union for Conservation of Nature (IUCN) if they were a species of animal, I don’t see us ever describing and naming all insects, let alone all organisms.

Diversity of that magnitude makes your head spin, but here I am only fortunately only concerned with organisms that can be readily seen without the aid of microscopes, which has plenty of diversity for the casual naturalist to cope with. Thefocus with our garden is to make it ‘pollinator friendly’, and I am pleased to say that we have a vibrant and varied community of pollinators. The obvious way of doing this is of course to plat a variety of favoured flowering plants so that nectar and pollen sources are available throughout the summer. But there are other ways to enhance pollinators as well. For example, those pesky weed flowers in your lawn are actually important for many pollinators – a perfectly manicured lawn is not! For example, a number of solitary bee species nest in the ground, so if you have a lush, weed free lawn, you are depriving them

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A small bee in the species-rich Family Andrenidae. These bees are solitary and nest in burrows in the soil.

of nesting habitat. If you want wild pollinators, it is important to provide areas where they can nest, e.g., areas with bare soil or sparse vegetation. Our lawn is neglected at best, which leaves it thin enough in spots to serve as nesting sites for mining bees and sweat bees (Family Andrenidae and Halictidae, respectively). I also keep mason bees, so called because they separate their brood cells with a mud wall, and consequently they need a source of mud to create those walls.

Many species of bumble bee use abandoned mouse burrows for nesting; they may

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A queen of the striking yellow-faced bumble bee, Bombus vosnesenskii, about to enter a rodent burrow to nest in. This species is now one of the most common species on Vancouver Island

occasionally use artificial bumble bee boxes, but the occupancy rate tends to be very low. A recent student talk out of Gerhard Gries’ lab at my Alma Mater, Simon Fraser University, may offer some hope for improvement, however, so I intend to give some bumble bee boxes a try next year. I won’t give anything away here though – stay tuned for official news from the student doing the work!

The word “pollinator” is generally associated with the word “bee”, which in turn is associated with the non-native, semi-domesticated honey bee, Apis mellifera. In terms of wild bees, there are close to 500 species, and likely more, in British Columbia alone (Sheffield and Heron 2018). Some are familiar to most people, particularly the eusocial species, e.g., bumble bees. The vast majority are solitary or communal, nesting in the ground or in wood. Examples of such bees include the leafcutter and mason bees (Megachilidae), miner bees (Andrenidae), and sweat bees (Halictidae), all of which are common. But pollinators include many other groups of insects. Members of another group of the Order Hymenoptera, the wasps also contribute to pollination to some extent, but not nearly as much as bees as they lack the adaptations for pollen collection. This vast group of Hymenoptera species comprises a plethora of interesting and often beautiful garden visitors. Some are predators, e.g., the yellowjackets and hornets, but most are parasitoids, which means that they use live insects or other arthropods as food for their larvae, but unlike the true parasites, the victim is eventually killed. The bee

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A bee wolf, Philanthus crabriformis

wolf, Philanthus crabroniformis (?), which is common here, uses various bees as hosts. Another common visitor is the American sand wasp, Bembix americana (Crabronidae), which uses flies to provision their nests. Occasionally, a green/blue  jewel will make an appearance.  This may be a cuckoo wasp (Chrysididae), which are kleptoparasites in the nests of other bees. They are heavily sclerotized and can roll up in a protective ball should they get attacked by the host species. There are way too many interesting species among the Hymenoptera, and I have to confess that the diversity is somewhat overwhelming, even to an entomologist.

Flies (Order Diptera) are particularly abundant flower visitors; they may not be as

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A hover fly, Family Syrphidae, in the genus Heliophilus.

efficient as bees, but they do contribute. Sometimes you may not realize that you are looking at a fly, rather than a bee or a wasp, because they can be convincing mimics. For example, hover flies (Family Syrphidae) are frequently black and yellow and can fool the casual observer. Non-mimic flies, like blow flies (Calliphoridae), flesh flies (Sarcophagidae), house flies (Muscidae) and parasitic flies (Tachinidae) are also frequent flower visitors, as are any number of smaller species. Another prominent and familiar group is the butterflies (which are even loved, unlike most other insects) and their nocturnal cousins, the moths (Order Lepidoptera). For most people, butterflies are always welcome visitors with their striking colours and dipsy-doodle flight. In our yard, the diversity has been somewhat disappointing. We have all three swallowtails that occur here (western tiger, Papilio rutulus; pale, P. eurymedon; and anise swallowtail, P. zelicaon), and we sometimes see Lorquin’s admiral, Limenitis lorquini, painted lady, V. cardui,

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Lorquin’s admiral, Limenitis lorquini

and frequently cabbage white, Pieris rapae. On one occasion each we have seen a mylitta crescent, Lycaena helloides, and a pine white butterfly, Neophasia menapia. We also have had three species in the family Lycaenidae (blues and coppers), and lots of woodland skippers, Ochlodes sylvanoides.  A great quick-guide to the butterflies of southern Vancouver Island is available. Finally, there are beetles, ants, and some other groups that may visit flowers more or less regularly. Some definitely contribute as pollinators, e.g., the Yellow Velvet Beetle, Lepturobosca chrysocoma (Cerambycidae, Lepturinae), while others may do little for the flower in the return for the treat.

Apart from pollinators, there are a host of other insects which are more or less welcome in a garden. In our garden, one that definitely falls in the latter category is the western subterranean termite (Reticulitermes hesperus). Builders have an annoying habit to bury

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Emergence of reproductive western subterranean termites, Reticulitermes hesperus

leftover wood around construction sites, which in areas with termites is essentially an invitation to the termites to move in. We have annual nuptial emergence events from our backyard lawn, and I have spent about $4,000 and considerable sweat equity to replace a retaining wall and a privacy screen fence which were close to falling down due to these little cellulose-consuming fiends.

Also in the Order Hymenoptera along with bees and wasps, ants are of course ever present. While I have only observed them casually, usually as we dig up a nest when planting something, we have a number of species from several genera in the subfamily Formicinae (Formica and Lasius spp.), a few in the Myrmicinae, (likely Myrmica and or Leptothorax spp.), and one species in the Dolichoderinae. This is the diminutive but pesky odorous house ant, Tapinoma sessile, a native ant that is a frequent home invader, widely distributed, and invasive in Hawaii (unfortunately a hotbed of exotic invaders; see my blog “A naturalist in Hawaii Part III: Attack by the aliens”).

Speaking of invasives, there is no shortage of exotic species in Nanaimo gardens. Some of the most obvious ones are the European paper wasp, Polistes dominula, which most non-biologists would simply call a yellowjacket wasp. These somewhat delicate and (fortunately) relatively non-aggressive wasps build open paper nests in any protected spot they can fine, e.g., my bat house. Another alien that shows up almost wherever you look is the European earwig, Forficula auricularia. While they can be a bit of a nuisance, these insects are actually quite interesting. They are thigmotactic (seek out tight cracks etc.), which led to the idea that they like to crawl into people’s ears, which may explain the odd common name. They have unique hind wings, which are normally folded under the tegmina (=leathery wing covers), which are modified forewings with the same function as the elytra of beetles. Earwig cerci have been modified as pincers, which they can use in defense, male dominance contests, to capture prey, and to help fold the wings. You can tell the sex of an earwig by looking at the pincers; females have relatively straight cerci, whereas in males they are curved.

One of my favourite exotics is the European wool carder bee, Anthidium manicatum. This

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European wool carder bee, Anthidium manicatum

member of the Family Megachilidae (leafcutter and mason bees) is rather entertaining as males patrol their favourite patch of flowers such as lamb’s ear, Stachys byzantina, chasing away anything that attempts to land. Lamb’s ear has very hairy leaves, and female wool carder bees collect the hairs to line their nests, which they establish in pre-existing cavities.

A number of beetle species are also exotics. Examples are Rhagonycha fulva (Cantharidae), an introduced soldier beetle from Europe, and Pterostichus melanarius, possibly the most common of all ground beetles, at least in urban and suburban areas. These species are fairly benign, but some new exotics that may cause severe economic damage are on their way, unfortunately. The brown marmorated stink bug, Halyomorpha halys, which has already arrived, and the spotted wing Drosophila, Drosophila suzukii, which is present in the Okanagan, have the potential to severely impact fruit and berry production on Vancouver Island. The stink bug, which is already established on the mainland and has been found on Vancouver Island, is also a significant nuisance insect where it has established in eastern North America. Also, a nest of the giant Asian hornet, Vespa mandarinia, was detected and destroyed recently in Nanaimo. If this species becomes established in BC, it could be very bad news for people and honey bees alike! Among intentially introduced exotics, the Cinnabar moth, Tyria jacobaeae, a biologial control agent of tansy ragwort, Jacobaea vulgaris, is eye-catching as both larvae and adults display aposematic colours. It also has the distinction of having given Cinnabar Valley its name!

I could go on for much longer, but I hope you get the gist – we have a lot of biodiversity right here in our backyard! If you pay attention, you are likely to find a lot more than you thought where you live! Start exploring the little creatures that run the world in addition to the charismatic (but species poor) megafauna!

References

Bertone, M.A., M. Leong, K.M. Bayless, T.L.F. Malow, R.R. Dunn, and M.D. Trautwein. 2016. Arthropods of the great indoors: characterizing diversity inside urban and suburban homes. PeerJ 4:e1582 https://doi.org/10.7717/peerj.1582

Forbes, A.A., R.K. Bagley, M.A. Beer, A.C. Hippee and H.A. Widmayer . 2018. Quantifying the unquantifiable: why Hymenoptera, not Coleoptera, is the most speciose animal order. BMC Ecology  18: 21, 11 pages  https://doi.org/10.1186/s12898-018-0176-x

Larsen, B.B., E.C. Miller, M.K. Rhodes, and J.J. Wiens. 2017. Inordinate fondness multiplied and redistributed: the number of species on earth and the new pie of life. The Quarterly Review of Biology 92: 229-265.

Mora, C., D.P. Tittensor, S. Adl, A.G.B. Simpson, and B. Worm. 2011. How many species are there on earth and in the ocean? PLoS Biology 9(8): e1001127. https://doi.org/10.1371/journal.pbio.1001127

Sheffield, C.S. and J.M. Heron. 2018. The bees of British Columbia (Hymenoptera: Apoidea, Apiformes). Journal of the Entomological Society of British Columbia 115: 44-85. https://journal.entsocbc.ca/index.php/journal/article/view/1001/1097

Stork, N.E. 2018. How many species of insects and other terrestrial arthropods are there on earth? Annual Review of Entomology 63: 31 -45.

Wilson, E.O., 1992. The effects of complex social life on evolution andbiodiversity. Oikos 63: 13–18.

 

 

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Observations by a Backyard Naturalist II: Invertebrates Other than Insects

“The question is not what you look at, but what you see.”

Henry David Thoreau

For as long as I can remember, insects, spiders and other arthropods have fascinated me.

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My typical pose as a kid.

Some of my earliest memories include watching huge European fishing spiders (Dolomedes fimbriatus) at a dock on a lake where my uncle had a cabin. Many years later I kept house spiders (Agelenidae) that I found in the basement of our apartment building in jars in my bedroom. I was fortunate to be able to turn this childhood fascination into a career.

In the first installment of this blog topic, I discussed vertebrates in our backyard in south Nanaimo. It is the invertebrates that really dominate in terms of diversity, however, and in this part I will focus on non-insect invertebrates. No matter how often you are out there looking, there are always new discoveries waiting for you. I have never been much of a collector, and in my old age I have developed an aversion to killing living even the tiniest of creatures, so I often cannot identify what I find. The emergence of iNaturalist has vastly improved the odds of identifying plants and animals, even if it often is only possible to Order, Family or Genus.

So what is out there? There are earth worms of course – most of these are actually invasive as most native species went extinct during the last ice age. See the eFauna checklist for specifics. If you look under pieces of wood, rocks and other moisture-retaining features, you will find a variety of organisms that require a moist environment

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Pillbugs, presumably Armadillidium vulgare, showing their ability to roll up. I am unsure what this pair was doing, perhaps mating!

to survive. Sowbugs and pillbugs, which are Crustaceans, i.e., they are related to crabs and shrimp, are very common. Two sowbug species, the European Sowbug (Oniscus asellus), and the Common Rough Woodlouse (Porcellio scaber), are particularly common under any piece of wood (hence one of the other many names, wood louse), and the Common Pill-bug (Armadillidium vulgare), is also relatively common. The latter rolls up into a ball like an armadillo when disturbed, which explains the generic name. All three are introduced. They have evolved behavioural, morphological and physiological adaptations for life out of water, with some groups having evolved several types of primitive lungs. Several species of centipede (Chilopoda) and millipede (Diplopoda) can also be found under rocks and pieces of wood, although one occasional visitor, the Yellow-spotted or Cyanide Millipede (Harpaphe haydeniana) can often be seen in the open. The name refers to defensive secretions, which are advertised by the millipede with its contrasting black and yellow aposematic (=warning) colours. Centipedes are predatory whereas millipedes are scavengers. They are quite easily separated as millipedes have two pairs of leg per segment (Greek diplos = double) whereas centipedes have one pair. The common names refer to their numerous legs, although neither lives up to the count indicated (100 and 1000, respectively). Together they make up the Subphylum Myriapoda.

Similar to the isopods, snails and slugs, the Pulmonates (Latin Pulmo = lung), which comprise a subgroup (previously a Subclass or Order) of the mollusk Class Gastropoda, are much too common. The name refers to the primitive “lung” they possess to enable them to live in a terrestrial environment. If you look carefully on a live slug or snail, you will see a small opening on the right side. This is the pneumostome (Greek pneumo = lung stóma = mouth ), through which air is drawn into the highly vascularized mantle cavity. In terms of species, introduced Grove snails (Cepaea nemoralis) vary from a plain brown

Grove snail

Light phase Grove snail.

shell to a pretty cream with or without dark stripes. Most striking among the slugs are the massive Pacific Banana slugs (Ariolimax columbianus), as well as large slugs in the Arion ater group, which are introduced. These giants can make quick work of plants, so they are usually unceremoniously moved into the field behind our yard.

The arachnid fauna, which has always fascinated me, is very diverse. Among my favourite group, the jumping spiders (Family Salticidae), I have found 4-5 species, the

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Salticus scenicus, the zebra jumping spider.

most common of which are the Zebra jumping spider (Salticus scenicus) and the Flat California jumper, Platycryptus californicus. The latter finds its way into the house with amazing regularity, and I generally leave them or gently move them outdoors. Jumping spiders have numerous characteristics that make them worthy of your attention. They are highly visual, some have shown astounding intelligence for such diminutive creatures, and their courting rituals are both fascinating and entertaining (I highly recommend a google search for ‘peacock spider’ videos by Jürgen Otto). Males in particular sometimes sport some pretty gaudy colours to charm the females, an evolutionary parallel to male birds. Wolf spiders (Family Lycosidae) are ever-present roaming hunters most often seen as they bask in the sun, scurrying into hiding at the slightest disturbance. Like the jumping spiders, they are highly visual, albeit not possessing the visual acuity of salticids. In the summer you may spot females carrying an egg sac around with them, and once the spiderlings emerge, she will let them hitchhike on her abdomen for a short period. This may surprise you, but in fact many types of spiders are very good mothers – the males do not contribute at all after mating, if they even survive that adventure!

The giant house spider, Eratigena atrica, a much less charming and somewhat scary-looking but harmless member of the Family Agelenidae, is another semi-frequent house guest. Females generally stay in their funnel webs, which they build in protected areas, so it is the males that make unwelcome appearances at times. The garage is home to numerous Cellar spiders (Pholcus phalangiodes), which are true spiders in the family Pholcidae, unlike the Harvestman ‘spiders’. False black widows, Steatoda grossa, which share the Family Theridiidae with its more famous Latrodectus species relatives, are generally making their homes in garages or basements. Like the black widows, false widows make tanglefoot webs that are ideal for ensnaring hapless passersby like ants, other spiders, or isopods.

Moving back outdoors, there is no end to the diversity. In the fall, orb web spiders in the family Aranaeidae become extremely common. The specimens we see most often are females, which with their more or less colourful swollen abdomens look more imposing

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An unknown species of orbweb spider in the genus Aranaeus

than they really are. As with many creatures around human habitation, it is an introduced species, the Cross spider, Araneus diadematus, that is the most common species on southern Vancouver Island. Another common (but rarely seen) introduction is the Woodlouse hunter, Dysdera crocata (Family Dysderidae), which sports massive (relative to the size of the spider) fang-armed chelicerae (jaws). This species can be encountered under wood or buried in loose soil, and as the name implies, it specializes on wood lice. Looking a little further up, specifically on flowers, you may find the common Goldenrod spider (Misumena vatia), a sit-and-wait predator that is a member of

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A female Goldenrod spider, Misumena vatia, with an unfortunate victim.

the crab spider family (Thomisidae). They have some limited ability to change colour to match the flower they are on. This species catches pollinators and other flower visitors, but the impact is not significant enough to cause any harm. While doing some clearing

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Brown-legged crab spider, Coriarachne brunneipes

up, I recently found a crab spider species I had not seen before, the Brown-legged Crab Spider (Coriarachne brunneipes). This very flat species is associated with wood, where it waits for potential prey. Shortly after I found this species, I also found a female Pacific Foldingdoor Spider (Antrodiaetus pacificus), one of the few mygalomorph spider species we have, which means it is related to tarantulas. They are characterized by fangs that move vertically. All other spiders are araneomorph with fangs that move laterally. The Pacific Foldingdoor spider builds burrows in soft soil or wood. During the day the entrance is covered with a silk door, but at night it is opened and the spider sits at the entrance waiting to rush out at passing beetles or other prey. Having poor eye-sight, it is alerted to the presence of prey by silk threads extending out from the burrow.

When you are small, staying alive is of course a priority. Several families of spider use the strategy of mimicry. Do you see an ant? Look closer, sometimes it may be a spider. Common around our place is one of the ground spiders (Family Gnaphosidae) in the

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An ant-mimic ground spider, likely Sergiolus columbianus. It may not look much like an ant, but part of the deception is behavioural, so it does a decent job when moving around.

genus Sergiolus (most likely S. columbianus). Some tropical species can be very ant-like, whereas most of our species tend to be less sophisticated.

There are lots of other groups of spiders, of course. In fact, spiders are some of the most abundant organisms on earth. It is said that you are never more than a meter or so from a spider. Fortunately for arachnophobes, they keep themselves to themselves most of the time, and they are completely harmless in spite of the frequent reports of spider bites, which are mostly caused by something else, but at best blamed on some innocent spider that happened to be nearby, and at worst just assumed (Bennett and Vetter 2004; Vetter and Isbister 2008). The largest group, the sheet-web spiders, Family Linyphiidae, were called money spiders in the UK because they were thought to bring good luck. These are generally tiny spiders that can occur in huge numbers. There small webs are often visible in grassy fields during the fall, when dew reveals their presence. The males in the Subfamily Erigoninae, can sport bizarre shapes on the prosoma (front part), including turrets for their eyes.  My point is that spiders deserve some respect. If you get to know them, you may even learn to like them!

References

Bennett, R.G., and R. S. Vetter. 2004. An approach to spider bites. Erroneous attribution of dermonecrotic lesions to brown recluse or hobo spider bites in Canada. Canadian Family Physician 50: 1098–1101.

Vetter R.S., and G.K. Isbister. 2008. Medical aspects of spider bites. Annual Review of Entomology. 53: 409-29.

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Observations by a Backyard Naturalist I: Vertebrates

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Winter view from our living room.

I am very fortunate to live in a semi-rural part of Nanaimo. From our living room, we look out at Richard Lake, a small, shallow lake surrounded by grass-covered land that gets flooded every winter. Extraction of peat appears to have been done in this area in the past, creating a number of additional ponds, which serve as habitat for various creatures. Our backyard backs onto the edge of this area, providing a naturalist’s paradise. This blog is an attempt to describe some of the animals that we have viewed in or from our property over the past 4 years.

Mammals. In terms of charismatic megafauna, we have our share of visitors. An American black bear (Ursus americanus) visited us two years in a row, scaling and damaging our fence in the process. The purpose of the visit was to gorge on apples, which I managed to capture with my trail camera. We are now more diligent in making sure that the apples are picked up, although climbing is something that black bears do exceedingly well, so we are certainly not completely bear-safe. Along with bears, we also have regular visits from

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Family of Black-tailed deer that took advantage of an open gate.

raccoons (Procyon lotor). Black-tailed deer (Odocoileus hemionug columbianus), a subspecies of mule deer, cannot get into the yard except when you leave the gate open. They enjoy munching on plants in the front yard to our consternation, however. We also see deer behind the yard on a semi-regular basis. From our yard, we regularly see North American river otters (Lutra canadensis) and beaver (Castor canadensis) on the lake, and on one occasion I also saw a mink (Neovison vison). Less charismatic (and all introduced) animals that use our backyard are eastern cottontail rabbits (Sylvilagus floridanus) (we do not have feral European rabbits (Oryctolagus cuniculus) where we live), both Norway (Rattus norvegicus – aka brown rat) and black rats (Rattus rattus – aka roof rat), mice (Mus musculus and perhaps other species), as well as gray squirrels (Sciurus carolinensis) that show up to raid my bird feeders from time to time. A few years ago I set up a bat house, and to my delight, a few bats use it every year. I don’t know which of the 9 or 10 Vancouver Island species frequent our area, but just having them around is good enough for me.

Bats of VI

Excerpt from “BC’s bat species” table published by Community Bat Programs of BC https://www.bcbats.ca/index.php/bat-basics/bc-bat-species

Bat caveat

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Black-headed grosbeak male, one of the most beautiful species.

Birds. Although I am an entomologist by profession, bird watching has always been a favourite pastime of mine. Luckily, our backyard and the marsh and lake behind our home provides ample opportunity to serve as my private hotspot. At the time of writing, my tally of species seen or heard from our yard is 86, which is very close to 1/3 of the 261 species listed for the entire Nanaimo region (just south of Nanaimo to Deep Bay along the east coast of Vancouver Island) in the recently revised Seasonal Bird

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Sharpshinned hawk resting after an unsuccessful raid of my bird feeders on a very miserable day.

Checklist published by the Arrowsmith Naturalist Club. Considering that a fair number of those are marine or high elevation species, and that as a casual birder I am likely to miss many species that are difficult to identify or are heard rather than seen (I normally get about ¾ or less than what ‘experts’ find), the proportion of Nanaimo region species may be 50% or perhaps even more. The species I have recorded so far (over close to 4 years) can be seen in the table below.

Birds at home table

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Willow flycatcher singing his heart out just behind our yard.

Reptiles and amphibians are rather scarce, but they do show up on a regular basis. Pacific Chorus Frogs (aka Pacific Tree Frog), Pseudacris regilla, can be heard year-round

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Pacific chorus frog

when the temperature is approaching 10 oC, but the best time is in May, when they really earn their name by serenading the neighborhood at full volume. The invasive American Bullfrog, Lithobates catesbeianus, rarely shows up in our yard, but its deep call can be heard in late spring – early summer when they breed. We are very pleased to have breeding Garter Snakes, Thamnophis spp., in our yard, although it does make mowing the lawn stressful as we worry about injuring these harmless and attractive snakes. The adults are relatively easy to spot, but the newly hatched snakes are only about 10 cm long, so they are easily overlooked. There are three species of garter snake on Vancouver Island, but the most likely species would be the Western Terrestrial (or Wandering) Garter Snake.

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This feisty little Western Terrestrial Garter Snake was found a few km away from our home, but this beautiful specimen deserves to represent the species. It responded to our presence by a rather convincing display of aggressiveness, although it didn’t bite when I picked it up and moved it to a safer location.

In the next installment of this blog, I will cover the invertebrates in our yard.

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The inertia of science

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Some of the greatest scientific advances have been made by maverick scientists; people who go off on tangents despite widely accepted existing paradigms. A paradigm is essentially an accepted framework that directs research to advance by an accumulation of solutions to problems. According to Thomas Kuhn, normal science operates within this framework. From time to time, a revolution may occur, which shifts the paradigm to create a more or less different framework. In other words, a paradigm describes our current understanding of something. But how do paradigms emerge? Most of the time they emerge through the accumulation of evidence through research carried out by scientists working within the relevant discipline. A proposal of a paradigm shift initially tends to be met with resistance, however, and acceptance is generally only the result of many years of research attempting to either prove or falsify the new idea. My first exposure to how this process can work was as an undergraduate student at the University of Umeå, Sweden, when I attended a lecture by a Nobel Laureate from a University in California. I can’t remember the name of the person (it was 45 years ago and these days I can’t remember names at all), but he was a brain neurophysiologist.  In his lecture, he stated that he habitually used to make controversial statements, knowing that it would cause a flurry of research to prove him wrong. He also said that he didn’t really care if he was right or wrong, but that it was a way to generate evidence that he couldn’t do on his own. Albert Einstein’s theory of relativity was also rejected, most famously in the German book “Hundert autoren gegen Einstein” (100 authors against Einstein). When asked about this book, Einstein responded “Why 100? If I were wrong, then one would have been enough!”

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Albert Einstein in 1947. Photograph by Orren Jack Turner, Princeton, N.J.

Sometimes paradigms are not based on accumulated evidence, however, but on opinions by highly regarded scientists expressing opinions that are accepted, perhaps because they make intuitive sense. An example from my own field is the widely held “truth” that bark beetle outbreaks invariably lead to forest fires. In this case, it appears that no empirical evidence was present to support this idea, and research over the past 10-20 years have shown that it is far from certain that bark beetle-caused mortality is followed by forest fire. There is no question that an accumulation of fuel will affect the progression of a forest fire once it occurs, but the prevalent paradigm while I was going through my education was that there was a cause and effect between bark beetles and the occurrence of fire.

An example is the theory of continental drift in the early twentieth century by Alfred Wegener https://www.livescience.com/37529-continental-drift.html . The problem for Wegener was that he lacked a mechanism by which his theory would work. Consequently, the idea met with considerable resistance and even ridicule. Opponents held fast to the idea that mountain chains on earth had been formed by continental contraction caused by the cooling of the earth, and that the continents were fixed in place. Fortunately, some scientists supported the idea, but it took almost 50 years, during which evidence supporting some of Wegener’s theory was collected and the idea of plate tectonics was put forth, before Princeton geologist Harry Hess proposed a mechanism in support of the idea that continents moved around. Thus, Wegener’s idea now lives on as the Theory of Plate Tectonics.

The motivation for writing this blog came from another example, much closer to my own field of study. In addition, I had thought about the issue on numerous occasions when research proposals or manuscripts submitted for publication were rejected simply because “that is not how it works”. The study that served as the ultimate trigger came via a book recommended to me by a colleague, “And no birds sing” by Mark Jaffe (not to be confused with “And no birds sang” by Farley Mowat). The book tells the story of then

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Brown tree snake (Boiga irregularis), Photo by Pavel Kirillov.  CC BY-SA 2.0, https://commons.wikimedia.org/w/index.php?curid=46853510

graduate student Julie Savidge (now a professor at Colorado State University), and her struggles to convince the establishment that the invasive Brown Tree Snake, Boiga irregularis, was the key culprit in the elimination of Guam bird species. One key opponent was a well-respected ornithologist, who rejected her findings on the basis that there was no precedence for a snake impacting fauna in this manner, and specifically, the brown tree snake was not known to have had any significant impact elsewhere. To make a long story short (read Jaffe’s book if you want the long version), Julie stuck to her guns and produced enough evidence to convert the doubters. Her persistence likely saved a few of the species of endemic Guam birds that were headed for certain extinction. The fight against the invasive snake carries on, e.g., https://www.guampdn.com/story/news/2017/07/30/drug-laced-mice-used-combat-brown-tree-snake/507382001/.

I was not a paradigm shifter, but still encountered some of the inertia of science as an author and editor. Criticism is obviously a good thing, and our peer review system improves science by exposing logical or methodological flaws. Outright rejection of ideas without a substantive argument to do so is not good, however. Many significant leaps forward in science have resulted from someone thinking “outside the box”. We need to keep an open mind, recognizing that knowledge is never complete and often context dependent. Sometimes we simply have it wrong, so there is always more to learn.

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Times have changed: dealing with dodgy science in the internet age

Important discussion by Manu Saunders‘ excellent blog “Ecology is not a dirty word” on how to prevent ‘dodgy’ science.

Ecology is not a dirty word

Dodgy science, dodgy scientists and dodgy humans are not a new thing. And dodgy scientific papers have been published since the dawn of scientific publishing. In 1667 an article on ‘snakestones’, a pseudoscience medical cure with absolutely no basis in truth, appeared in one of the first issues of the oldest known scientific journal, Philosophical Transactions of the Royal Society (now Phil Trans A, one of the most prestigious modern scientific journals).

Since then, disreputable papers have made regular appearances in reputable journals. And there are different scales of disreputable. The paper claiming that octopi originated from outer space was clearly far-fetched, while the scholars who recently argued there was a ‘moral panic’ over free-ranging cats simply highlighted how interdisciplinary research is often challenged by opposing methodological approaches (note: I agree with most ecologists that free-ranging cats are not good for wild animals, including insects).

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Harewood Plains – Nanaimo’s flowering jewel!

It has been a while since I wrote a blog. The splendour of Harewood Plains in bloom has provided the inspiration to get one done. I hope you enjoy it!

In late April through May, Harewood Plains in Nanaimo puts on a magical show with a bounty of flowering plants. This area, which stretches along the southwest of the southern portion of Nanaimo Parkway, from just uphill from Cranberry Road overpass to Harewood Mines Road overpass is unique because of its shallow soils creating a magical

Harewood Plains

Outline of Harewood Plains. The meadows in this Google Earth image appear as light brown areas. Access is from McKeown Way (off Extension Road) or Lotus Pinnatus Way (off Harewood Mines Road).

network of meadows that host a spectacular diversity of flowering plants. These are normally quite wet at this time  of year, but this year they are quite dry, which may affect some of the flowering species. The fields are usually dominated by a combination of sea blush (Plectritis congesta), monkey flower (Mimulus guttatus ) and common camas (Camassia quamash ) creating a spectacular pink, blue and yellow canvas. The careful observer will find lots of other flowers, however.  Among these are as many as 10 rare red- or blue-listed plants, including 80% of all bog bird’s-foot trefoil, Lotus pinnatus, in British Columbia.  Harewood Plains is one of only five locations for this red-listed species in Canada.

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Common Camas (Camassia quamash) in full bloom in the foreground with Sea blush and Monkey flowers in the distant background.

Over the past two years I have visited different parts of the Harewood Plains to observe the wonder of the flowering meadows, as well as the insects that take advantage of the bounty. In most cases I have been able to identify the flowers, but there are some tricky ones, for sure. Surprisingly, there is no comprehensive checklist or pictorial key of Harewood Plains flowers on the internet, which provides an opportunity to create a resource that is accessible to the public. As incumbernt President of Nature Nanaimo, I have suggested that we undertake such a project over the next few years. Stay tuned for updates!

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Sea blush (Plectritis congesta) with Monkey flowers (Mimulus guttatus) in the background. In this photo Common camas are not yet in bloom, but their slender leaves can be seen in the foreground.

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Yellow monkey-flower (Mimulus guttatus) brightens up the Plains with large groups of bright yellow flowers.

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Death camas (Toxicoscordion venenosum) surrounded by Sea blush. While Common camas was an important food source for First nations, Death camas is not edible, as the name clearly states!

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Spring gold (Lomatium utriculatum) and Sea blush.

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Western trillium (Trillium ovatum) grows in more shaded locations. Flowers can be white or pink, and occasionally maroon.

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Common camas visited by a Western spring azure (Celastrina echo)

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Chocolate lily (Fritillaria camschatcensis) grows in small groups.

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Look closer and you may find the gorgeously delicate Alaska saxifrage (Saxifraga ferruginea).

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Fawn lily (Erythronium oregonum) flowers early and can be found in richer sites in scattered groups of up to a few dozen plants.

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Broad-leaved stonecrop (Sedum spathulifolium) can be found in various places. This specimen grew under a Douglas-fir near Lotus pinnatus Park.

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If you venture into the forest, you may find the spotted coralroot (Corallorhiza maculata), a fascinating orchid. It is a myco-heterotroph, which means that it acquires its nutrients from fungal mycelia from fungi in the Order Russulaceae. Hence, it lacks photosynthetic tissues, and lives as a parasite!

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If you look closer, you will find numerous small, but beautiful flowers, sometimes with equally small and beautiful visitors. These Scouler’s popcornflowers (Plagiobothrys scouleri) are visited by a longhorned fairy moth (Adela septentrionella), which are common at Harewood Plains in May.

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The same species of flower visited by a Cedar hairstreak (Callophrys nelsoni).

These are just a very small sample of species that I managed to identify, hopefully correctly. This is the time of year to get out and enjoy the show.

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The long, burning hot summer: The new normal?

During one week this past summer, I was largely confined inside my home due to extremely poor air quality. The air had been hazy with fine particulate matter from hundreds of forest fires burning throughout British Columbia, including one only 10 km from my home in Nanaimo, BC. The summer weather has been hot and dry, turning our forests into a giant tinderbox, poised to catch fire from the most unlikely sources.

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The influence of forest fires is not restricted to destructive burning. This is a photo of the smoke blanketing Prince George, BC, in 2010 from a fire 120 km to the west.

Lightning strikes have caused a larger than usual number of these fires, but human activity has still accounted for a quarter of the fires, which is somewhat less than the 40% average over the past 10 years. Pieces of glass that focus the sun’s rays, and cigarette butts are among the culprits linked to humans, as are illegal camp fires and flares of all things. A report on CBC Radio One indicated that people are still not getting the message that it is critically important to obey the fire bans that are in effect throughout the province, and to refrain from smoking or discarding cigarette butts by throwing them on the ground. No matter how much you stomped on it, there is no guarantee that it is truly out! This report from last year’s record fire season is a clear indication that campers frequently ignore campfire bans. Each fire forces fire fighters to risk their lives in order to keep us safe, and each new fire diverts both human and physical resources from other fires. The fires also consume a natural resource that is central to British Columbia’s economy, leading to loss of jobs and revenue. In addition, the enormous costs of fire-fighting deplete funds that could be better used to solve a housing crisis that grips many communities in southwestern BC, or for improvements to health care and education. That is money that comes from taxes, so it is baffling that people do not care when in essence, they are hurting their own economic prospects! In 2017, a record $560 million was the estimated cost of the worst fire season the province had ever experienced at that time. As of the end of August, however, 2018 had surpassed the previous year, and was ranked as the worst fire season in BC’s history with an astounding 13,000 square km (1,351,314 ha to be precise) affected. The cost will possibly to be slightly lower, however, because the fires were more remote and therefore threatened fewer human habitations.

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BC Fire map as of August 20, 2018. Copyright BC Wildfire Service.

The blame for fires has often been placed on bark beetle outbreaks, global climate change, and/or clearcutting. While some of those factors can certainly play a role in terms of the severity and spread of the fire, neither is the root cause (clearcutting is probably beneficial for slowing fires, rather than a contributing agent). Lately, there has been an increase in accusing the government over poor forest management and inadequate responses to the fires, and not only by Donald Trump. It is certainly understandable that affected citizens are looking for simple answers and someone to blame, but unfortunately it is more complex than that. In order for fire to become a problem, favourable weather (=drought and wind), abundant fuel, and an ignition source have to co-occur. Last year essentially presented us with the perfect storm in that regard. Fire scientists in Canada can predict the risk of a wildfire occurring by using the Canadian Forest Fire Danger Rating System, which is based on 14 data inputs in 6

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Structure of the Fire Weather Index system. See http://cwfis.cfs.nrcan.gc.ca/background/summary/fwi  for details.

categories, including moisture, topography, fuels, and weather. In part, predictions allow for planning to ensure that resources are in place to fight fires, should they occur, but they are also there to alert the public to take precautions. In spite of this, 2 of 5 fires are completely preventable if people heeded the warnings and fire bans. In the past few years, that is about $200 million per year that taxpayers have to cover. And this does not include the downstream costs, e.g., lost revenue for forest companies and businesses, health issues arising from smoke etc.

BC was not the only victim of historic fires. California and Australia suffered as they often do, but even my native Sweden, where a forest fire less than 10 ha is first page news (although historically, large areas were often burned), 20,000 hectares went up in flames, prompting firefighters from numerous EU countries to send help. This is in a country where road access is generally very good (allowing prompt response to any fire), forests are intensively managed, and the climate tends to be relatively cool, and sometimes quite wet. In the 26+ years I lived in Sweden, I never saw a forest fire.  Here in Canada, I have seen numerous forest fires, but apart from the 2003 Okanagan Mountain Park fire, the last 2 years have been exceptional. And it is unlikely to get better.

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Ashcroft reserve fire at Loon lake, BC. Photo: Shawn Cahill, Creative Commons Attribution-Share Alike 4.0 International license.

Fires release carbon dioxide into the atmosphere, which leads to further warming. A particularly disturbing sign is that normally perpetually wet ecosystems, like northwestern Vancouver Island, also experienced a significant number of severe fires. Now Australia is experiencing severe heat, breaking records and killing animals. The warning signs are clear, but politicians worldwide seem to only pay lip-service to the problem with global climate change, even after IPCC warned that we are quickly approaching a precipice.

When a planet dies in the universe, does anybody care?

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