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Blackberries

Fermenting Apples & Black Bears ≠ Inebriation

11-5-18 bear scat MH_20091011_233455_4If you investigate the contents of Black Bear scat this time of year, you may well find nothing but chunks of digested and semi-digested apple (pictured).  For several weeks before hibernation begins bears spend their days and nights foraging for food that will sustain them through the coming months (“hyperphagia”).  Fermenting apples lying on the ground are accessible and very popular with bears; hence, many scats contain them.

There have been anecdotal reports over the years of Black Bears stumbling around as if inebriated, and it is often assumed that this behavior is the result of their having consumed fermenting fruit, such as apples.  Waxwings, robins and other species of birds are known to get drunk (and even die) from fermented crab apples, mountain ash and blackberries, but it’s highly unlikely that bears follow suit.

For one thing, the pH of a bear’s stomach is around 3.5 – slightly more acidic than yeast can tolerate. In addition, the time it takes for a Black Bear to digest food is typically far less time than yeast would need to convert sugar into alcohol. Lastly, size would play a large role in an animal’s ability to become intoxicated. It would take hundreds of apples consumed at their peak level of fermentation to make even a small, young Black Bear even slightly tipsy.

If you see a Black Bear stumbling and acting strange it may well be because it is sleepy or perhaps sick, but probably not drunk. However, until researchers test the blood alcohol level of a bear that’s exhibited this behavior, no–one can say for sure what caused it.

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Blackberry Psyllids Heading for Conifers

11-9-15 blackberry psyllid 101Occasionally you see a wild Blackberry bush with leaves that have stunted growth and are often curled up. This malformation is due to the Blackberry Psyllid (Trioza tripunctata), also known as the Jumping Plant Louse. Closely related to aphids and scale insects, psyllids are plant-feeding bugs which typically have one specific host on which they feed and lay their eggs. Blackberry Psyllids, small, cicada-like insects that hold their wings tent-like over their body, feed only on Blackberry and in so doing, cause this leaf distortion.

Blackberry Psyllids have one generation per year. The adults mate and lay eggs (39-202) on Blackberry bushes in early summer. The nymphs, small and wingless, also feed on the sap of Blackberries. They are often found inside the curled leaves during the summer months where they secrete several types of waxy structures as they feed. In the fall the nymphs mature and overwinter as adults in conifers (pines, spruces and cedars) prior to returning to Blackberry bushes in the spring. If Blackberries are one mile or more from conifers, no psyllid damage will be found; those growing within one-eighth of a mile from conifers are at the greatest risk of psyllid damage.

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Black Bears Seeking Protein

9-2 hornet nest torn by bear 083Although insects and animal matter make up less than 10% of the annual black bear diet, they are a crucial part of it. Black bears get most of their animal protein from ant brood, hornet larvae, tent caterpillars, march fly larvae, grubs (especially June beetle grubs), and snow fleas. Among the most preferred sources are bee and hornet larvae. Berries and other fruit don’t have a great amount of protein, but they do have some (blackberries = 2 grams of protein per cup). If the summer berry crops fail, insect brood is especially important, especially at this time of year, when bears are seeking protein, fats and carbohydrates, putting on as much as 30 pounds per week to sustain themselves through the coming months of hibernation.

When tearing apart a beehive, yellow jacket nest or bald-faced hornet nest (see photo), bears do get stung, particularly on their ears and faces (their fur is fairly impenetrable). Apparently the reward is worth the aggravation. After filling themselves with brood (and in some cases, honey) black bears shake vigorously in order to rid themselves of any insects that are caught in their fur.(Thanks to Alfred Balch for photo op.)

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