Maternal effects on offspring growth rate and weaning mass in harbour seals

2001 ◽  
Vol 79 (6) ◽  
pp. 1088-1101 ◽  
Author(s):  
W Don Bowen ◽  
Sara L Ellis ◽  
Sara J Iverson ◽  
Daryl J Boness
Keyword(s):  
Growth Rate ◽  
Nova Scotia ◽  
Path Analysis ◽  
Maternal Effects ◽  
Maternal Age ◽  
Mass Gain ◽  
Phoca Vitulina ◽  
Young Females ◽  
Harbour Seals ◽  
Offspring Growth

We studied maternal effects on offspring traits during lactation in harbour seals (Phoca vitulina) on Sable Island, Nova Scotia, from 1988 to 1996. Duration of lactation was correlated with rate of pup mass gain (r = %#150;0.34, n = 116) and weaning mass (r = 0.29, n = 154). Pups that grew faster had shorter nursing periods, whereas those that attained higher weaning masses nursed for a greater number of days. Pup sex did not affect patterns of maternal effects. The pups of young females (4%#150;6 years old) gained mass at a constant but lower rate (0.56 kg/d) than the pups of older females through midlactation (0.74%#150;0.78 kg/d; n = 75). In older females, rates of pup mass gain decelerated between mid and late lactation. Although maternal age did not directly affect weaning mass of pups, path analysis showed that maternal age acted on weaning mass through intermediary traits. Lighter females gave birth to smaller and slower growing pups, but invested relatively more than heavier females (n = 153). Effects of maternal postpartum mass on weaning mass (n = 100) were weaker in harbour seals than in phocids that fast during lactation, but apparently stronger than in otariids that forage during lactation, suggesting that the strength of maternal effects is influenced by lactation strategy.

The effect of maternal age and other factors on birth mass in the harbour seal

1994 ◽  
Vol 72 (1) ◽  
pp. 8-14 ◽  
Author(s):  
W. D. Bowen ◽  
O. T. Oftedal ◽  
D. J. Boness ◽  
S. J. Iverson
Keyword(s):  
Nova Scotia ◽  
Developmental Stage ◽  
Body Mass ◽  
Maternal Age ◽  
Phoca Vitulina ◽  
Harbour Seal ◽  
Birth Date ◽  
Young Mothers ◽  
Maternal Body ◽  
Harbour Seals

We studied the effects of maternal age, maternal body mass at parturition, year of birth, birth date, pup sex, and developmental stage (as indicated by the presence of a foetal pelage called lanugo) on the birth mass of harbour seals (Phoca vitulina) on Sable Island, Nova Scotia, Canada. Between 1987 and 1992, mass was obtained on 330 newborns and 259 of their mothers. Birth mass was significantly correlated with maternal mass (r = 0.42 for male pups; r = 0.32 for female pups). Among pups that had shed their lanugo, males were significantly heavier at birth (11.4 ± 0.09 kg, n = 107) than females (10.9 ± 0.09, n = 99). Birth mass increased significantly with maternal age (n = 71, range 4–12 years) even after the effects of maternal mass and pup sex were statistically removed. Mean birth mass varied significantly among years, from 10.5 to 11.5 kg. Newborns averaged 12.8% of maternal mass at parturition (84.8 ± 0.49 kg). Most (84%) pups had shed their lanugo before birth. Pups born with extensive lanugo were born earlier in the season and weighed about 20% less than pups born without lanugo. These data suggest that pups born with lanugo may be less developed than pups that had shed their foetal coat. Young mothers (4 and 5 years old) produced most of the underweight, lanugo-covered pups.

scholarly journals The role of maternal age and context-dependent maternal effects in the offspring provisioning of a long-lived marine teleost

2018 ◽  
Vol 5 (1) ◽  
pp. 170966 ◽  
Author(s):  
Linsey M. Arnold ◽  
Wade D. Smith ◽  
Paul D. Spencer ◽  
Allison N. Evans ◽  
Scott A. Heppell ◽  
...  
Keyword(s):  
Maternal Effects ◽  
Maternal Age ◽  
Narrow Range ◽  
Somatic Growth ◽  
Age Effects ◽  
Offspring Quality ◽  
Young Females ◽  
Context Dependent ◽  
Intrinsic Function

Despite evidence of maternal age effects in a number of teleost species, there have been challenges to the assertion that maternal age intrinsically influences offspring quality. From an evolutionary perspective, maternal age effects result in young females paradoxically investing in less fit offspring despite a greater potential fitness benefit that might be gained by allocating this energy to individual somatic growth. Although a narrow range of conditions could lead to a maternal fitness benefit via the production of lower quality offspring, evolutionary theorists suggest these conditions are seldom met and that the reported maternal age effects are more likely products of the environmental context. Our goal was to determine if maternal effects operated on offspring provisioning in a long-lived rockfish (genus Sebastes ), and to evaluate any such effects as an intrinsic function of maternal age or a context-dependent effect of the offspring release environment. We found that offspring provisioning is a function of both maternal age and the timing of offspring release; older females exhibit increased provisioning over younger females throughout the spawning season despite a decrease in provisioning across all maternal ages as the season progresses. These findings suggest a role for both maternal age effects and a potential context-dependent maternal effect in population productivity, carrying important implications when modelling population persistence and resilience.

Observations on a Colony of Whelping Harbour Seals, Phoca vitulina concolor, on Sable Island, Nova Scotia

1971 ◽  
Vol 28 (5) ◽  
pp. 755-759 ◽  
Author(s):  
Jean Boulva
Keyword(s):  
Nova Scotia ◽  
Phoca Vitulina ◽  
Harbour Seals ◽  
Seal Population ◽  
Males And Females

Three censuses indicated that approximately 1220 harbour seals were at Sable Island at the beginning of whelping in 1970. About 270 pups were born, representing 18% of the total seal population after whelping. Maximum whelping occurred during the last week of May. Males represented 52% of the 118 pups examined. At least 12% of the pups died in the 1st month of life. Pups born with lanugo represented 16% of all pups born. Males and females averaged 80 cm long and 11 kg in weight at birth; 3 weeks later, the males averaged 91 cm and 24 kg and the females 86 cm and 20 kg.

scholarly journals Maternal Age and Maternal Environment Affect Egg Composition, Yolk Testosterone, Offspring Growth and Behaviour in Laying Hens

2021 ◽  
Author(s):  
Tina M. Widowski ◽  
Leanne Cooley ◽  
Simone Hendriksen ◽  
Mariana R.L.V. Peixoto
Keyword(s):  
Maternal Effects ◽  
Maternal Age ◽  
Laying Hens ◽  
Egg Yolk ◽  
Maternal Environment ◽  
Testosterone Concentration ◽  
Natural Decrease ◽  
Offspring Growth ◽  
Egg Composition ◽  
Yolk Testosterone

Abstract Maternal effects have been reported to alter offspring phenotype in laying hens. In this study, we investigated the effects of maternal environment and maternal age on egg traits and offspring development and behaviour. For this, we ran two experiments. First (E1), commercial hybrid hens were reared either in aviary or barren brooding cages, then housed in aviary, conventional cages or furnished (enriched) cages, thus forming different maternal housing treatments. Hens from each treatment were inseminated at three ages, and measures of egg composition, yolk testosterone concentration and offspring’s development, anxiety and fearfulness were assessed. In experiment 2 (E2), maternal age effects on offspring's growth and behaviour were further investigated using fertile eggs from commercial breeder flocks at three ages. Results from E1 showed that maternal age affected the majority of measures including egg composition, yolk testosterone, offspring growth, anxiety and fearfulness. Maternal rearing and housing affected fewer measures but included egg characteristics, offspring weight and behaviour. Effects of maternal age were not replicated in E2, possibly due to higher tolerance to maternal effects in commercial breeders. Overall, our research confirms that maternal environment and maternal age affect the offspring of laying hens in a variety of ways. These effects may be mediated by the natural decrease in egg yolk testosterone concentration over time.

Testing predictions of optimal diving theory using animal-borne video from harbour seals (Phoca vitulina concolor)

2014 ◽  
Vol 92 (4) ◽  
pp. 309-318 ◽  
Author(s):  
Susan G. Heaslip ◽  
W. Don Bowen ◽  
Sara J. Iverson
Keyword(s):  
Nova Scotia ◽  
Temporal Pattern ◽  
Dive Depth ◽  
Dive Duration ◽  
Phoca Vitulina ◽  
Encounter Rate ◽  
Harbour Seals ◽  
Wide Range ◽  
Oxygen Stores ◽  
Free Ranging

Optimal diving theory predicts that animals make decisions that maximize their foraging profitability subject to the constraint of oxygen stores. We examined the temporal pattern of prey encounters within a dive from concurrently collected dive data and animal-borne video from a free-ranging pinniped to test predictions of optimal diving theory. Crittercams were deployed on 32 adult male harbour seals (Phoca vitulina concolor De Kay, 1842) at Sable Island, Nova Scotia, Canada, for 3 days each. Deployments resulted in approximately 3 h of video per seal and a total of 2275 capture attempts for 1474 prey encounter events recorded. We found support for seven of the nine selected predictions of optimal diving theory. As predicted, prey encounters increased with bottom duration; dive duration increased with dive depth; and travel duration, bottom duration, and percent bottom duration decreased over a wide range of travel durations. Descent duration did increase with dive depth, and seals terminated dives earlier when no prey were encountered and when prey were encountered later in a dive. Contrary to prediction, bottom duration did not increase and then decrease for short travel durations and dives were not terminated earlier when travel durations were short and prey encounter rate was low.

Diving behaviour of lactating harbour seals and their pups during maternal foraging trips

1999 ◽  
Vol 77 (6) ◽  
pp. 978-988 ◽  
Author(s):  
W D Bowen ◽  
D J Boness ◽  
S J Iverson
Keyword(s):  
Nova Scotia ◽  
Post Partum ◽  
Dive Duration ◽  
Phoca Vitulina ◽  
Diving Behaviour ◽  
Early Lactation ◽  
Adult Females ◽  
Harbour Seals ◽  
Lactating Females

Female harbour seals (Phoca vitulina) undertake foraging trips during mid to late lactation. We show that they are accompanied by their pup during many of these foraging trips. Time-depth recorder data were obtained from 20 lactating females and 14 of their pups in 1995 and 1996 at Sable Island, Nova Scotia. Overall, females spent 55.4 ± 4.68% (mean ± SE) of their time at sea compared with 39.8 ± 2.29% for pups. Like those of their mothers, pups' dives occurred in clusters or bouts: 71.4 ± 4.4 dives, 2.5 ± 0.15 h in duration. Bouts of diving by females and pups began 0-3 days post partum. Mean dive duration of pups increased from about 1 to 1.5 min over the course of lactation, but was still shorter than that of adult females (1.5-2.25 min). Both females and pups appeared to dive within their theoretical aerobic dive limits (TADL) of 8.9 and 2.6-3.1 min, respectively. Up to 3.6% of dives by some pups may have exceeded their TADL. Pups appeared to compensate for their lesser diving ability by making more and shorter dives per bout than females, particularly during early lactation.

scholarly journals Anopheles gambiae maternal age and parous state control offspring susceptibility to Plasmodium falciparum

2020 ◽  
Author(s):  
Christian Mitri ◽  
Isabelle Thiery ◽  
Marie-Thérèse Lecoq ◽  
Catherine Thouvenot ◽  
Solange Touron ◽  
...  
Keyword(s):  
Plasmodium Falciparum ◽  
Anopheles Gambiae ◽  
Malaria Transmission ◽  
Maternal Effects ◽  
Maternal Age ◽  
Gonotrophic Cycle ◽  
State Control ◽  
Reproductive State ◽  
Young Females ◽  
Old Females

AbstractMaternal effects have been reported in many organisms whereby exposure to environmental stress, either toxics or pathogens will impact on progeny response to these stresses. Here we show that Anopheles gambiae susceptibility to Plasmodium falciparum is dependent upon maternal effects driven by females not previously exposed to the parasite. The maternal effect involved both mother age and reproductive state. Offspring of old females or from a 4th gonotrophic cycle are more susceptible than offspring from young females. These maternal effects also contribute to overall better fitness of the offspring. As mosquito population age structure contributes heavily shaping malaria transmission, consequences of this novel finding should be taken into account in further strategies for controlling malaria transmission.

The influence of underwater data transmission sounds on the displacement behaviour of captive harbour seals (Phoca vitulina)

2006 ◽  
Vol 61 (1) ◽  
pp. 19-39 ◽  
Author(s):  
Ronald A. Kastelein ◽  
Sander van der Heul ◽  
Willem C. Verboom ◽  
Rob J.V. Triesscheijn ◽  
Nancy V. Jennings
Keyword(s):  
Data Transmission ◽  
Phoca Vitulina ◽  
Harbour Seals
Sign in / Sign up

Export Citation Format

Share Document