Editing Elephant seal (section)

==Life history==
The average lifespan of a northern elephant seal is 9 years, while the average lifespan of a southern elephant seal is 21 years.<ref>{{Cite web|url=http://www.nationalgeographic.com/animals/mammals/group/elephant-seals/|archive-url=https://web.archive.org/web/20170223010928/http://www.nationalgeographic.com/animals/mammals/group/elephant-seals/|url-status=dead|archive-date=February 23, 2017|title = Elephant Seals &#124; National Geographic|website = [[National Geographic Society]]|date = 10 May 2011}}</ref> Males reach maturity at five to six years, but generally do not achieve [[Alpha male|alpha]] status until the age of eight, with the prime breeding years being between ages 9 and 12. The longest life expectancy of a male northern elephant seal is approximately 14 years.

Females begin breeding at age 3–6, and have one pup per breeding attempt.<ref>{{Cite journal|last=Huber|first=Harriet R.|date=1987-06-01|title=Natality and weaning success in relation to age of first reproduction in northern elephant seals|journal=Canadian Journal of Zoology|volume=65|issue=6|pages=1311–1316|doi=10.1139/z87-207|issn=0008-4301}}</ref> Most adult females breed each year.<ref name=":0">{{Cite journal|last=Lee|first=Derek E.|date=2011-06-09|title=Effects of environmental variability and breeding experience on northern elephant seal demography|journal=Journal of Mammalogy|volume=92|issue=3|pages=517–526|doi=10.1644/10-MAMM-A-042.1|issn=0022-2372|doi-access=free}}</ref> Breeding success is much lower for first-time mothers relative to experienced breeders.<ref name=":0" /> Annual survival probability of adult females is 0.83 for experienced breeding females, but only 0.66 for first-time breeders indicating a significant cost of reproduction.<ref name=":0" /> More male pups are produced than female pups in years with warmer [[sea surface temperature]] in the northeastern Pacific Ocean.<ref>{{Cite journal|last1=Lee|first1=Derek E.|last2=Sydeman|first2=William J.|date=2009|title=North Pacific Climate Mediates Offspring Sex Ratio in Northern Elephant Seals|journal=Journal of Mammalogy|language=en|volume=90|issue=1|pages=1–8|doi=10.1644/08-MAMM-A-130.1|issn=0022-2372|doi-access=free}}</ref>

Females and males utilize different feeding strategies in order to maximize their reproductive success. Males feed in [[Benthic zone|benthic]] regions with more abundant food sources, but also more abundant predators. Females feed in [[Pelagic zone|pelagic]] regions where they are less likely to find prey, but also less likely to be preyed upon. They employ these different strategies because females are smaller, requiring less food, and it is also most important for them to have as many breeding seasons as possible in order to maximize reproductive success. On the other hand, males can adopt a riskier strategy in the hopes of gaining as much mass as possible, and thus being able to have one extremely successful breeding season.<ref>{{Cite journal |last1=Kienle |first1=Sarah S. |last2=Friedlaender |first2=Ari S. |last3=Crocker |first3=Daniel E. |last4=Mehta |first4=Rita S. |last5=Costa |first5=Daniel P. |date=January 2022 |title=Trade-offs between foraging reward and mortality risk drive sex-specific foraging strategies in sexually dimorphic northern elephant seals |journal=Royal Society Open Science |volume=9 |issue=1 |page=210522 |doi=10.1098/rsos.210522 |pmid=35116140 |pmc=8767210 |bibcode=2022RSOS....910522K |s2cid=246018225 |issn=2054-5703|doi-access=free }}</ref>