Oc­to­ber is an­i­mal fat­ten­ing time (Wikewiku’s)

The Victoria Standard - - Environment - ANNAMARIE HATCHER

The days are be­com­ing shorter, the leaves more colour­ful and many an­i­mals are get­ting fat­ter as sum­mer fades and au­tumn tight­ens its’ hold on the Bras d’or Lake Bio­sphere. In the Mi’kmaw cal­en­dar Oc­to­ber is Wikewiku’s, or an­i­mal fat­ten­ing month. This is a ‘time of plenty’ in terms of food sup­plies for many an­i­mals but that sit­u­a­tion will change dra­mat­i­cally as the ground freezes and is then cov­ered with a white blan­ket of snow. The fat that is ac­cu­mu­lated at this time of year will sus­tain the an­i­mals that hi­ber­nate all win­ter. Hiber­na­tion is a fas­ci­nat­ing adap­ta­tion that is nec­es­sary for the sur­vival of many species in this cli­mate. Some of the Bio­sphere’s an­i­mals re­main in ‘sus­pended an­i­ma­tion’ all win­ter and some wake up and eat dur­ing the warmer pe­ri­ods of win­ter. The lit­tle brown bat (Mi’kmaq: na’jipug­taq’nej), once com­mon in the Bio­sphere, is a true hi­ber­na­tor, slow­ing down its me­tab­o­lism, heart rate, and breath­ing. It wakes pe­ri­od­i­cally to drink or elim­i­nate waste and it re­lies solely on its fat re­serves to sur­vive from Septem­ber to April (fe­males) or May (males). Dur­ing hiber­na­tion, a brown bat's pulse de­creases from 400-700 beats per minute to 7-10. A bat will put on weight (fat) be­fore go­ing into hiber­na­tion, dou­bling or even tripling its weight! Au­tumn is mat­ing sea­son for the lit­tle fly­ing mam­mals and in the past, large groups would fly in from their sum­mer lo­ca­tions and gather in caves and mines to eat and mate. Sounds like a party! The pop­u­la­tion is sparse now be­cause of the dev­as­tat­ing ef­fects of the white nose syn­drome. The clouds of fly­ing bats that were ev­i­dent in some ar­eas of the Bio­sphere in Oc­to­ber are now gone.

Did you ever won­der what strat­egy the Bio­sphere’s chip­munks (Mi’kmaq: apalqaqamej) em­ploy to sur­vive dur­ing the cold win­ter pe­riod? In Oc­to­ber, they are busily gath­er­ing food and stor­ing it. When the cold days of Novem­ber and De­cem­ber set in, they dis­ap­pear be­low ground to their bur­rows. They then go into a tor­pid state where body tem­per­a­ture, rate of breath­ing, and rate of heart­beat drop to very low lev­els. Un­like the lit­tle brown bat, they don’t fat­ten up in au­tumn but store their food for oc­ca­sional snack­ing. Pe­ri­ods of tor­por of­ten last from one to eight days. Be­tween these pe­ri­ods, chip­munks wake up and con­sume part of the food sup­ply which they stored in their bur­rows in the au­tumn. In March, when the air is warm­ing and the maple sap is flow­ing, the chip­munks be­gin to emerge, some­times hav­ing to bur­row up­wards through deep snow.

One of the more charm­ing Bio­sphere hi­ber­na­tors is the Black bear (Mi’kmaq: Muin). Au­tumn is a time for them to fat­ten up be­fore the long win­ter’s sleep. The Black bears slum­ber in their dens for about five to seven months without eat­ing, drink­ing, uri­nat­ing, or defe­cat­ing. Their bod­ies get a lit­tle cooler but the tem­per­a­ture drop is not nearly as sig­nif­i­cant as it is in other hi­ber­nat­ing an­i­mals. Their heart rates drop from 55 to 9 beats a minute. Their eyes will be open when awake but they might be groggy. If this oc­curred in a hu­man, they would faint. How­ever, the bear’s phys­i­ol­ogy is adapted to this metabolic de­crease. The bear’s body es­sen­tially be­comes a self-con­tained unit dur­ing the win­ter slow-down. Urine is bro­ken down in­side their body and reused as pro­tein to help main­tain mus­cles and a plug of fae­ces and hair forms at the end of the di­ges­tive tract to keep ev­ery­thing in. The av­er­age bear loses about 3.6 kg per week dur­ing this pe­riod, re­ly­ing on those fat re­serves laid down dur­ing the ‘an­i­mal fat­ten­ing time’ in au­tumn. While the di­ges­tive tract is es­sen­tially closed, the re­pro­duc­tive tract re­mains func­tional.

Fe­male Black bears of­ten give birth dur­ing hiber­na­tion. Mother and cubs emerge from the den in the spring, none the worse for wear. To some­one who has de­liv­ered three sons, this sounds like an ap­peal­ing birth plan.

So, as I strug­gle to fit into my jeans af­ter Thanks­giv­ing din­ner I will re­mind my­self that my body is just pre­par­ing for hiber­na­tion as many of the Bio­sphere in­hab­i­tants are.

Dr. Annamarie Hatcher is an ad­junct pro­fes­sor at Unama’ki Col­lege, Cape Bre­ton Univer­sity, and a board mem­ber of the Bras d’or Lake Bio­sphere Re­serve As­so­ci­a­tion. For more in­for­ma­tion about the Bras d’or Lake Bio­sphere Re­serve As­so­ci­a­tion, please visit http://blbra.ca/.

The hiber­na­tion cy­cle of the Black bear is used to ex­plain the sea­son­ally-chang­ing po­si­tion of the con­stel­la­tion Ursa Ma­jor in the Mi’kmaw leg­end ‘Muin and the Seven Bird Hun­ters’.

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