An online resource based on the award-winning nature guide

Archive for June, 2018

Insect Populations Decline In Number And Diversity

6-27-18 common milkweed IMG_7097Thirteen years ago I went and sat in a field full of Common Milkweed (Asclepias syriaca). The photographs I took of insects visiting the fragrant blossoms ended up being the subject of my first children’s book, Milkweed Visitors. The number and diversity of invertebrates in that patch of milkweed was astounding. Over a decade later I find milkweed flowers alarmingly free of insect visitors. I first noticed this several years ago, and unfortunately the trend has continued. An occasional honey bee or bumblebee, perhaps a swallowtail butterfly or a red milkweed beetle or two can be seen, but nowhere near the number or variety of insects that you found just a few years ago.

Recent studies show that insect populations are declining dramatically not only in milkweed patches, and not only in North America, but in many parts of the world. A global index for invertebrate abundance showed a 45 percent decline over the last four decades. (Yale School of Forestry and Environmental Studies). Researchers say various factors, from the rampant use of pesticides (in particular, neonicotinoids), the spread of monoculture crops such as corn and soybeans, urbanization, and habitat destruction contribute to this decline.

This phenomenon affects everything from pollination to the documented decline in bird populations that feed on flying insects. However, thus far, only the decline of honey bee populations has received widespread public attention, in large measure because of their vital role in pollinating food crops. The rest of the insect world has been widely ignored. Insects play a major role not only in pollination but as predators of insect pests and as food for birds, amphibians and bats. Who knows how many plant species live in symbiotic relationships with highly specialized insects.

Given the importance of insects for agriculture, biodiversity and the health of ecosystems, one hopes that studies regarding the decline of insects will increase in the near future.  We can all contribute to a greater understanding of what is happening by participating in “citizen science” projects which undertake monitoring of specific insect species. A list of such projects and how to get involved can be found at https://xerces.org/citizen-science/.

Naturally Curious is supported by donations. If you choose to contribute, you may go to https://naturallycuriouswithmaryholland.wordpress.com and click on the yellow “donate” button.

 


Loon Cartoon

Submitted by chiropractor extraordinaire, Susan Kellogg.

loon cartoon from Susan Kellogg IMG_0969 (002)


Image

Five-day-old Common Loon Chick Seeking Shelter & Rest

6-27-18 common loon chick3


Common Loon Chicks Hatching

6-27-18 loon chicks3_U1A9901

Newly-hatched Common Loon chicks can swim as soon as they hit the water, which they do as soon as their down dries after hatching, usually within 24 hours. Their buoyancy and lack of maneuverability, however, leave them vulnerable to predators. Parents usually don’t stray far from their young chicks due to the omnipresent threat of eagles, hawks, gulls, large fish and snapping turtles.  During their first two weeks, young loon chicks often seek shelter (and rest) on the backs of their parents.

Naturally Curious is supported by donations. If you choose to contribute, you may go to https://naturallycuriouswithmaryholland.wordpress.com and click on the yellow “donate” button.


Male Green Frogs Defending Territories

6-25-18 green frogs2 _U1A9296Male Green Frogs are extremely territorial. During June, July and August they establish a series of territories, often claiming each one for less than one week before moving on.

The desirability of a given territory is of utmost importance – the better the quality (amount of vegetation) of your territory the more likely it is that a female will choose you to fertilize her eggs. The more time a male spends in a high quality territory the greater the number of mates he will acquire.

Considerable aggression is displayed against other males when an individual is claiming and maintaining a territory. When a competing male arrives, a wrestling match often ensues (see photo).

Naturally Curious is supported by donations. If you choose to contribute, you may go to https://naturallycuriouswithmaryholland.wordpress.com and click on the yellow “donate” button.


Vulnerable Ducklings

6-20-18 woody & ducklings IMG_8636

There is a reason why ducklings remain with their mother for their first month or two of life. It takes 50-70 days before most ducklings can fly, and survival during this period is highly variable, ranging from less than 10 percent to as high as 70 percent. They are at their most vulnerable during this stage. The most common causes of duckling mortality include predation, adverse weather conditions, starvation, disease, and parasites. The mother offers her young a degree of protection from some of these factors while they are under her care.

Predation is arguably the greatest threat to young waterfowl. Ducklings are sought after by nearly every type of predator, including other birds (eagles, hawks, owls, herons, crows), fish (largemouth bass and northern pike), amphibians (bullfrogs), reptiles (snakes and snapping turtles), and mammals (foxes, raccoons, and mink).  Their odds for survival increase dramatically when the ducklings obtain the ability to fly.  (Photo: female Wood Duck and ducklings)

Naturally Curious is supported by donations. If you choose to contribute, you may go to https://naturallycuriouswithmaryholland.wordpress.com and click on the yellow “donate” button.

 

 

 

 

 

 


The Emerald Euphoria Beetle: A Distinctive Scarab

6-20-18 emerald euphoria beetle_U1A8526

Beetles comprise almost 40% of described insects and 25% of all known animal life-forms. There are about 30,000 beetles known as scarabs or scarab beetles in the family Scarabaeidae. They make up about 10% of all known beetles. You may be very familiar with scarab beetles without even being aware that that is what they are – they are as close as the nearest Japanese Beetle or June Bug (beetle).

Scarabs are generally oval-shaped and stout. The smallest are about .08 inches and the largest (Hercules beetles) can reach 6.7 inches. Most scarabs are black or brown, but many, especially tropical species, have bright colors and intricate patterns. They have distinctive, clubbed antennae composed of plates called lamellae that can be compressed into a ball or fanned out like leaves to sense odors (see photo). Their diet is extremely varied and includes plant material, fungi, fruit, carrion, insects and even the slime left by snails.

One fruit- and flower-eating species is the Emerald Euphoria beetle, Euphoria fulgida (pictured). It is usually bright green or bluish. Emerald Euphoria beetles belong to the subfamily Cetoniiae, the flower or fruit chafers. One of its most distinctive characteristics is its ability to fly (using its second pair of wings) while its first pair (the hardened, colorful elytra) remain closed — most beetles open and extend their elytra during flight.

Unlike most scarabs, Emerald Euphorias are diurnal, making it possible to see this species visiting flowers in order to consume nectar, pollen and petals.  (Thanks to Richard Wyatt for photo op.)

Naturally Curious is supported by donations. If you choose to contribute, you may go to https://naturallycuriouswithmaryholland.wordpress.com and click on the yellow “donate” button.