Springtime flowers for springtime bees!

As insects begin to become active in the spring, one of the first things they need to do is find a food source. Spring wildflowers are one of the earliest food sources for many insects, but they are especially important for the bees that gather the nectar and pollen from these flowers to feed their offspring. 
Willow flowers are one of the first places you'll see a lot of bees on a sunny day in the spring. The larger bee in the picture below is a honey bee (Hymenoptera: Apidae, Apis mellifera) and the smaller bee is a halictid bee (Hymenoptera: Halictidae).  Springtime is a very important time of year for social bees like honey bees and bumble bees because this is the time of year when they start to build up their colonies of hundreds and thousands of worker bees that will collect resources for the hive all summer. 

This bee (below) might be a species of Ceratina (Hymenoptera: Apidae, Ceratina sp.), commonly called the small carpenter bee because they excavate holes in the stems of pithy plants in order to build their nests. 

Many plants, like willow, provide nectar and pollen that is easily accessible by a variety of insects. Other plants, however, make it a little bit harder for insects to get at that sweet sweet nectar. The flower pictured below, called a fringed polygala (Polygala sp.) requires a bee to land on a specific part of the flower in order to access its nectar. 

The polygala flowers are mainly pollinated by bumble bees because they are the only bees heavy enough to trip the mechanism that opens the flower and that have a long enough tongue to reach the nectar at the bottom of the long nectar tube. 

In order to access the nectar and pollinate the polygala flower, a bee has to land on the purple fringed structure at the tip of the lower petals. This will open up the flower to expose the pistil and stamens, which the bee will contact as it reaches its tongue down into the corolla to drink nectar from the base of the flower. 

Another of my favorite spring flowers, Spring Beauty (Claytonia spp.,below), is not so picky when it comes to choosing its pollinators. 

As you can see the pistil and stamens of this flower are right out there for any insect to access, and the corolla is not long and narrow, so they don't need a long tongue to get at the nectar. 

Interestingly, however, there is a bee that only gathers nectar and pollen from spring beauty and almost no other flowers. It is called the spring beauty bee (Hymenoptera: Andrenidae, Andrena erigeniae) and it is a solitary bee that nests in the soil under the leaf litter in forests where spring beauty grows. I didn't get a photo of one so I won't spend too much time on it today, but you can count on a future post on this charming little bee. 
Thanks for reading!

How to: help the bees!

An article I saw yesterday about how bees might be harmed by neonicotinoid pesticides reminded me to put up my wild bee house in my front yard.

This is an easy thing you can do at your home to help some of the wild bees in your neighborhood. If you live somewhere with four seasons, early spring is the best time of year to put out a bee house, but you can really do it any time of year, anywhere. Then enjoy watching as bees start to fill it up with nests!

This type of nest will only attract certain kinds of bees called stem-nesting or cavity-nesting bees, but its a great start to your home pollinator protection program. Stem-nesting bees are solitary bees, which means that they don't make large nests like the social bees (e.g. honey bees and bumble bees). 

Honey bee Apis mellifera

Honey bee hives in a blueberry field

Bumble bee Bombus sp.

A solitary bee entering her nest

Solitary bees also don't aggressively defend their nests, which means that they are much less likely to sting you or your family. I made my bee house out of an empty steel can, but any container that is impermeable to water and open on one end will work just fine. Size doesn't matter much either, although it should be at least 15 centimeters (6 in.) long or a little bit longer to protect the nest entrances from the rain. One important consideration is the direction that the nest faces. It is best if the open end or the bee house faces toward the east so that the sun warms it in the morning. However, if its not convenient to hang yours facing due east don't worry about it, the bees will probably still use it. I filled mine with a variety of nesting options to increase the diversity of the bees that will nest there. Bees can be pretty picky about their nesting sites, so if you only have one size nest hole you might only get one kind of bee. Easy options for nesting sites are sections of hollow reeds (e.g. bamboo) or blocks of wood with holes drilled in them. The tunnels for the bees should be about 15 cm (6 in.) deep and anywhere from 3 to 7 mm (1/8 to 1/4 in.) in diameter. If you're feeling really ambitious you can create a bee hotel with a variety of different nesting options.

Now if this post has piqued your interest, I recommend that you look at a couple of fact sheets that were produced by the Xerces society and provide more detailed information on Nests For Native Bees and Tunnel Nests For Native Bees. Good luck and have fun!

First insect sighting of the year!

This stonefly (Order: Plecoptera) ran out in front of me on the trail last weekend. It was one of the warmest days of the year so far (7 C, 44 F) so I was hoping to see some insect activity. This one was very active and I could barely keep up with it running across the snow, but it did pause long enough on the tip of my finger to get a good picture of its wings. Stoneflies have the scientific name Plecoptera (pleco-, folded or plaited; -ptera,wing), which refers to the way that the adult's hindwing is folded beneath the forewing. 

Stonefly larvae (AKA nymphs) live under the water where they eat algae, plants, or other insects. The adults emerge at different times of year depending on what species they are. I'm pretty sure this adult is a winter stonefly (Family: Taeniopterygidae). They tend to emerge from January to April. Insects have some amazing abilities when it comes to surviving and remaining active when temperatures are very cold. 

Stonefly adults are one of the few insects you will see in a cold winter day, but I think this one is a sign that spring is on its way!

The insect life cycle and metamorphosis

Yes, it's February and in the northern hemisphere that means it's very cold outside (-22 C, -8 F this morning to be exact). Too cold for insects to do much of anything, so I have decided to take this opportunity to create a post about the insect life cycle. 

All insects begin life as an egg. This picture shows a cluster of insect eggs on the underside of a leaf. The tiny wasp on the eggs is a parasitoid looking to lay some eggs of her own inside the other insect's eggs.

 If all goes well the eggs will hatch, and insect larvae will emerge. 
Insect larvae come in many shapes and sizes.

Below are several larvae of the darkling beetle (Coleoptera:Tenebrionidae) species Zophobas morio. The smaller ones to the left are the younger larvae and the one on the far right is very close to becoming an adult insect. 
(The scale on the bottom half of the ruler is in centimeters.)

As the insect larvae grow, they must shed their hard exoskeleton in a process called ecdysis. Following ecdysis the larvae are very pale colored and they must wait for their new exoskeleton to harden. A larva in this state is referred to as a teneral larva (shown below).

Once a larva has reached its full size and the time is right it will shed its last larval exoskeleton and enter the pupal stage.

 In these two photos (below), you can see a pupa emerging from its last larval exoskeleton. 

The insect pupa is not very active as it undergoes the process 

of metamorphosis from larva to adult.

 Following pupation, the insect will undergo one final ecdysis and emerge as an adult. The adult pictured below has recently emerged from the pupal exoskeleton. Much like a recently emerged larva, the adult beetle must wait for its exoskeleton to harden.

As the exoskeleton hardens, it also darkens to black and this darkling beetle is finally ready to begin its adult insect life.

Now, I should mention that not all insects follow this progression from egg-larva-pupa-adult. This is just one example of what entomologists call complete metamorphosis (or a holometabolous life cycle). In a future post, I will try to run the hemimetabolous life cycle, but for now please feel free to peruse the Wikipedia links that I have provided. 

Thanks for reading!